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Example 6
Ceres cDNA 12723147 encodes an Arabidopsis putative aldo/keto reductase. Ectopic expression of Ceres cDNA 12723147 under the control of the CaMV35S promoter induces the following phenotypes:
Wild-type Arabidopsis Wassilewskija (WS) plants were transformed with a Ti plasmid containing cDNA 12723147 in the sense orientation relative to the CaMV35S constitutive promoter. The Ti plasmid vector used for this construct, CRS338, contains PAT and confers herbicide resistance to transformed plants. Ten independently transformed events were selected and evaluated for their qualitative phenotype in the T1 generation. No positive or negative phenotypes were observed in the T1 plants.
Screens of Superpools on High PEG, Mannitol, and ABA as Surrogate Screens for Drought Tolerance.
Seeds from 13 superpools (1,200 T2 seeds from each superpool) from the CaMV35S or 32449 over-expression lines were tested on 3 drought surrogate screens (high concentrations of PEG, mannitol, and ABA) as described above. T3 seeds were collected from the resistant plants and analyzed for resistance on all three surrogate drought screens.
Once cDNA 12723147 was identified in resistant plants from each of the three surrogate drought screens, the five individual T2 events containing this cDNA (SR01013) were screened on high PEG, mannitol, and ABA to identify events with the resistance phenotype.
Superpools (SP) are referred to as SP1, SP2 and so on. The letter following the hyphen refers to the screen (P=PEG, M=mannitol, and A=ABA) and the number following the letter refers to a number assigned to each plant obtained from that screen on that superpool. For example, SP1-M18 is the 18th plant isolated from a mannitol screen of Superpool 1.
Qualitative and Quantitative Analysis of 2 Independent Events Representing 35S::cDNA 12659859 (SR01010) on PEG, Mannitol and ABA
To identify two independent events of 35S::cDNA 12659859 showing PEG, mannitol, and ABA resistance, 36 seedlings from each of two events, SR01013-01 and -02 were screened as previously described. BastaR segregation was assessed to verify that the lines contained a single insert segregating in a 3:1 (R:S) ratio as calculated by a chi-square test (Table 6-1). Both lines (01 and 02) segregated for a single insert in the T2 generation (Table 1)
Lines SR01013-01 and -02 were chosen as the two events because they had a strong and consistent resistance to PEG, mannitol and ABA. The controls were sown the same day and in the same plate as the individual lines. The PEG (Tables 6-2 and 6-3), mannitol (Tables 6-4 and 6-5) and ABA (Tables 6-6 and 6-7) segregation ratios observed for SR01013-01 and -02 are consistent with the presence of single insert as demonstrated by chi-square, similar to what we observed for BastaR resistance (Table 6-1).
The progeny from one resistant T2 plant from each of these two events were tested in the same manner as the T2. Resistance to PEG, mannitol and ABA was also observed in the T3 generation. Taken together, the segregation of resistant seedlings containing cDNA 12723147 from two events on all three drought surrogate screens and the inheritance of this resistance in a subsequent generation, provide strong evidence that cDNA 12723147 when over-expressed can provide tolerance to drought.
Example 2
PAO1, the parent strain of PGN5, is a wild-type P. aeruginosa strain that produces relatively small amounts of alginate and exhibits a non-mucoid phenotype; thus, PGN5 is also non-mucoid when cultured (
To examine whether the alginate produced by PGN5+mucE was similar in composition to alginate produced by VE2, HPLC was performed to compare the M and G content of alginate produced by each strain. The chromatograms obtained from alginate prepared from VE2 and PGN5+mucE were identical (
Example 2
A. Seed Treatment with Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the isolated microbe as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the isolated microbe applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiably higher biomass than the control corn plants.
The biomass from the treated plants may be about 1-10% higher, 10-20% higher, 20-30% higher, 30-40% higher, 40-50% higher, 50-60% higher, 60-70% higher, 70-80% higher, 80-90% higher, or more.
The biomass from the treated plants may equate to about a 1 bushel per acre increase over the controls, or a 2 bushel per acre increase, or a 3 bushel per acre increase, or a 4 bushel per acre increase, or a 5 bushel per acre increase, or more.
In some aspects, the biomass increase is statistically significant. In other aspects, the biomass increase is not statistically significant, but is still quantifiable.
B. Seed Treatment with Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the microbial consortium as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the microbial consortium applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiably higher biomass than the control corn plants.
The biomass from the treated plants may be about 1-10% higher, 10-20% higher, 20-30% higher, 30-40% higher, 40-50% higher, 50-60% higher, 60-70% higher, 70-80% higher, 80-90% higher, or more.
The biomass from the treated plants may equate to about a 1 bushel per acre increase over the controls, or a 2 bushel per acre increase, or a 3 bushel per acre increase, or a 4 bushel per acre increase, or a 5 bushel per acre increase, or more.
In some aspects, the biomass increase is statistically significant. In other aspects, the biomass increase is not statistically significant, but is still quantifiable.
C. Treatment with Agricultural Composition Comprising Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the agricultural composition will exhibit a quantifiably higher biomass than the control corn plants.
The biomass from the treated plants may be about 1-10% higher, 10-20% higher, 20-30% higher, 30-40% higher, 40-50% higher, 50-60% higher, 60-70% higher, 70-80% higher, 80-90% higher, or more.
The biomass from the treated plants may equate to about a 1 bushel per acre increase over the controls, or a 2 bushel per acre increase, or a 3 bushel per acre increase, or a 4 bushel per acre increase, or a 5 bushel per acre increase, or more.
In some aspects, the biomass increase is statistically significant. In other aspects, the biomass increase is not statistically significant, but is still quantifiable.
D. Treatment with Agricultural Composition Comprising Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the agricultural composition will exhibit a quantifiably higher biomass than the control corn plants.
The biomass from the treated plants may be about 1-10% higher, 10-20% higher, 20-30% higher, 30-40% higher, 40-50% higher, 50-60% higher, 60-70% higher, 70-80% higher, 80-90% higher, or more.
The biomass from the treated plants may equate to about a 1 bushel per acre increase over the controls, or a 2 bushel per acre increase, or a 3 bushel per acre increase, or a 4 bushel per acre increase, or a 5 bushel per acre increase, or more.
In some aspects, the biomass increase is statistically significant. In other aspects, the biomass increase is not statistically significant, but is still quantifiable.
A. Seed Treatment with Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the isolated microbe as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the isolated microbe applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiable and superior ability to tolerate drought conditions and/or exhibit superior water use efficiency, as compared to the control corn plants.
The drought tolerance and/or water use efficiency can be based on any number of standard tests from the art, e.g leaf water retention, turgor loss point, rate of photosynthesis, leaf color and other phenotypic indications of drought stress, yield performance, and various root morphological and growth patterns.
B. Seed Treatment with Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the microbial consortium as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the microbial consortium applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiable and superior ability to tolerate drought conditions and/or exhibit superior water use efficiency, as compared to the control corn plants.
The drought tolerance and/or water use efficiency can be based on any number of standard tests from the art, e.g leaf water retention, turgor loss point, rate of photosynthesis, leaf color and other phenotypic indications of drought stress, yield performance, and various root morphological and growth patterns.
C. Treatment with Agricultural Composition Comprising Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the with the agricultural composition will exhibit a quantifiable and superior ability to tolerate drought conditions and/or exhibit superior water use efficiency, as compared to the control corn plants.
The drought tolerance and/or water use efficiency can be based on any number of standard tests from the art, e.g leaf water retention, turgor loss point, rate of photosynthesis, leaf color and other phenotypic indications of drought stress, yield performance, and various root morphological and growth patterns.
D. Treatment with Agricultural Composition Comprising Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the with the agricultural composition will exhibit a quantifiable and superior ability to tolerate drought conditions and/or exhibit superior water use efficiency, as compared to the control corn plants.
The drought tolerance and/or water use efficiency can be based on any number of standard tests from the art, e.g leaf water retention, turgor loss point, rate of photosynthesis, leaf color and other phenotypic indications of drought stress, yield performance, and various root morphological and growth patterns.
A. Seed Treatment with Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the isolated microbe as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the isolated microbe applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiable and superior ability to utilize nitrogen, as compared to the control corn plants.
The nitrogen use efficiency can be quantified by recording a measurable change in any of the main nitrogen metabolic pool sizes in the assimilation pathways (e.g., a measurable change in one or more of the following: nitrate, nitrite, ammonia, glutamic acid, aspartic acid, glutamine, asparagine, lysine, leucine, threonine, methionine, glycine, tryptophan, tyrosine, total protein content of a plant part, total nitrogen content of a plant part, and/or chlorophyll content), or where the treated plant is shown to provide the same or elevated biomass or harvestable yield at lower nitrogen fertilization levels compared to the control plant, or where the treated plant is shown to provide elevated biomass or harvestable yields at the same nitrogen fertilization levels compared to a control plant.
B. Seed Treatment with Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as a seed coating to seeds of corn (Zea mays). Upon applying the microbial consortium as a seed coating, the corn will be planted and cultivated in the standard manner.
A control plot of corn seeds, which did not have the microbial consortium applied as a seed coating, will also be planted.
It is expected that the corn plants grown from the seeds treated with the seed coating will exhibit a quantifiable and superior ability to utilize nitrogen, as compared to the control corn plants.
The nitrogen use efficiency can be quantified by recording a measurable change in any of the main nitrogen metabolic pool sizes in the assimilation pathways (e.g., a measurable change in one or more of the following: nitrate, nitrite, ammonia, glutamic acid, aspartic acid, glutamine, asparagine, lysine, leucine, threonine, methionine, glycine, tryptophan, tyrosine, total protein content of a plant part, total nitrogen content of a plant part, and/or chlorophyll content), or where the treated plant is shown to provide the same or elevated biomass or harvestable yield at lower nitrogen fertilization levels compared to the control plant, or where the treated plant is shown to provide elevated biomass or harvestable yields at the same nitrogen fertilization levels compared to a control plant.
C. Treatment with Agricultural Composition Comprising Isolated Microbe
In this example, an isolated microbe from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the agricultural composition will exhibit a quantifiable and superior ability to utilize nitrogen, as compared to the control corn plants.
The nitrogen use efficiency can be quantified by recording a measurable change in any of the main nitrogen metabolic pool sizes in the assimilation pathways (e.g., a measurable change in one or more of the following: nitrate, nitrite, ammonia, glutamic acid, aspartic acid, glutamine, asparagine, lysine, leucine, threonine, methionine, glycine, tryptophan, tyrosine, total protein content of a plant part, total nitrogen content of a plant part, and/or chlorophyll content), or where the treated plant is shown to provide the same or elevated biomass or harvestable yield at lower nitrogen fertilization levels compared to the control plant, or where the treated plant is shown to provide elevated biomass or harvestable yields at the same nitrogen fertilization levels compared to a control plant.
D. Treatment with Agricultural Composition Comprising Microbial Consortia
In this example, a microbial consortium, comprising at least two microbes from Tables 1-3 will be applied as an agricultural composition, administered to the corn seed at the time of sowing.
For example, it is anticipated that a farmer will apply the agricultural composition to the corn seeds simultaneously upon planting the seeds into the field. This can be accomplished, for example, by applying the agricultural composition to a hopper/bulk tank on a standard 16 row planter, which contains the corn seeds and which is configured to plant the same into rows. Alternatively, the agricultural composition can be contained in a separate bulk tank on the planter and sprayed into the rows upon planting the corn seed.
A control plot of corn seeds, which are not administered the agricultural composition, will also be planted.
It is expected that the corn plants grown from the seeds treated with the agricultural composition will exhibit a quantifiable and superior ability to utilize nitrogen, as compared to the control corn plants.
The nitrogen use efficiency can be quantified by recording a measurable change in any of the main nitrogen metabolic pool sizes in the assimilation pathways (e.g., a measurable change in one or more of the following: nitrate, nitrite, ammonia, glutamic acid, aspartic acid, glutamine, asparagine, lysine, leucine, threonine, methionine, glycine, tryptophan, tyrosine, total protein content of a plant part, total nitrogen content of a plant part, and/or chlorophyll content), or where the treated plant is shown to provide the same or elevated biomass or harvestable yield at lower nitrogen fertilization levels compared to the control plant, or where the treated plant is shown to provide elevated biomass or harvestable yields at the same nitrogen fertilization levels compared to a control plant.
The inoculants were prepared from isolates grown as spread plates on R2A incubated at 25° C. for 48 to 72 hours. Colonies were harvested by blending with sterile distilled water (SDW) which was then transferred into sterile containers. Serial dilutions of the harvested cells were plated and incubated at 25° C. for 24 hours to estimate the number of colony forming units (CFU) in each suspension. Dilutions were prepared using individual isolates or blends of isolates (consortia) to deliver 1×105 cfu/microbe/seed and seeds inoculated by either imbibition in the liquid suspension or by overtreatment with 5% vegetable gum and oil.
Seeds corresponding to the plants of table 15 were planted within 24 to 48 hours of treatment in agricultural soil, potting media or inert growing media. Plants were grown in small pots (28 mL to 200 mL) in either a controlled environment or in a greenhouse. Chamber photoperiod was set to 16 hours for all experiments on all species. Air temperature was typically maintained between 22-24° C.
Unless otherwise stated, all plants were watered with tap water 2 to 3 times weekly. Growth conditions were varied according to the trait of interest and included manipulation of applied fertilizer, watering regime and salt stress as follows:
Untreated (no applied microbe) controls were prepared for each experiment. Plants were randomized on trays throughout the growth environment. Between 10 and 30 replicate plants were prepared for each treatment in each experiment. Phenotypes were measured during early vegetative growth, typically before the V3 developmental stage and between 3 and 6 weeks after sowing. Foliage was cut and weighed. Roots were washed, blotted dry and weighed. Results indicate performance of treatments against the untreated control.
The data presented in table 15 describes the efficacy with which a microbial species or strain can change a phenotype of interest relative to a control run in the same experiment. Phenotypes measured were shoot fresh weight and root fresh weight for plants growing either in the absence of presence of a stress (assay). For each microbe species, an overall efficacy score indicates the percentage of times a strain of that species increased a both shoot and root fresh weight in independent evaluations. For each species, the specifics of each independent assay is given, providing a strain ID (strain) and the crop species the assay was performed on (crop). For each independent assay the percentage increase in shoot and root fresh weight over the controls is given.
Example 1
119 Dicty strains were screened for their ability to feed on Dickeya (Dd) or Pectobacterium (Pcc) at 10° C. This assay was performed by inoculating Dd or Pcc on a low nutrient medium (SM2 agar) that supports both bacterial and Dicty growth. Dicty spores from individual strains were then inoculated on top of the bacterial growth and incubated at 10° C. to mimic potato storage temperatures. Dicty strains that successfully fed on Dd or Pcc created visible clearings in the lawn of bacterial growth and ultimately produced sporangia (fruiting bodies) that rose from the agar surface. An example of the phenotype that was considered successful clearing of bacteria is shown in
Of the 36 strains capable of feeding on both Dd and Pcc, 34 came from the Group 4 Dictyostelids (
A further experiment was performed to identify Dicty species capable of feeding on biofilms of Dd and Pcc. Microporous polycarbonate membranes (MPMs) are widely reported to support biofilm formation of numerous Enterobacteriaceae species (2, 63, 70, 71). It was determined if Dd and Pcc formed biofilms on MPMs and determined if Dicty strains were capable of feeding on these biofilms. Membranes were placed on top of SM2 agar to provide Dd and Pcc with nutrients for growth. Bacteria were then inoculated on the surface of the MPMs and growth was monitored over the course of 1 week by washing bacteria off the membranes and performing dilution plating for colony counting. Growth of both bacterial strains plateaued around 4 dpi (
From these results, it was determined that the best time to collect inoculated MPMs for biofilm analysis was at 2 dpi. Scanning electron microscopy (SEM) is commonly used to confirm biofilm formation by detecting extracellular polymeric substance (EPS) that forms the biofilm matrix (2). Samples of Dd and Pcc after 2 days of growth on MPMs in the presence and absence of Dicty are analyzed using SEM.
19 Dicty strains identified as active were tested for their ability to feed on Dd and Pcc growing on MPMs. These experiments were performed by establishing Dd and Pcc growth on MPMs overlaid on SM2 agar at 37° C. for 24 hr. Dicty spores were then applied to the center of bacterial growth in a 5 uL drop containing 1000 spores. Bacteria and Dicty were incubated at 10° C. for 2 weeks before remaining bacteria were washed off and colonies were counted. Representative images of Dicty growing on Dd and Pcc on MPMs are shown in
No Dicty strains produced a statistically significant reduction in Dd viability compared to the non-treated control. However, treating Dd lawns with Cohen 36, Cohen 9, WS-15, WS-20, and WS-69 consistently reduced the number of viable bacteria by approximately 100,000-fold compared to the non-treated control (
It was observed that Dicty strains Cohen 9, Cohen 36, and WS-69 were capable of feeding on both Dd and Pcc when these bacteria were cultured on SM2 agar and MPMs (
To determine if these strains could suppress soft rot development on seed potato tubers, tubers were tab-inoculated with Dd or Pcc and treated with spores from each Dicty strain. Seed potatoes were surface-sterilized and punctured using a sterile screw to a depth of 1.5 mm. Overnight cultures of Dd and Pcc were suspended in 10 mM potassium phosphate buffer, diluted to an OD600 of approximately 0.003, and administered as a 5 μL drop into the wound. Next, 5 of a Dicty spore suspension (100,000 spores) was added to the wound. Inoculated seed potatoes were placed in a plastic container with moist paper towels and were misted with water twice a day to maintain a high humidity. After 3 days at room temperature, seed potatoes were sliced in half and the area of macerated tissue was quantified using ImageJ.
All three strains reduced the severity of soft rot caused by Dd and Pcc (
Dicty should be capable of sporulating at temperatures as cold as 10° C. on a potato surface if they are applied as a one-time pre-planting or post-harvest treatment. Sporulation was assessed by inoculating small potato discs (5×6 mm) with 10 μL of Dd or Pcc suspensions at an OD600 of 3×10−5 and Dicty spores at a concentration of 1×107 spores/mL. Potato discs were kept in a covered 96-well plate for two weeks at 10° C. followed by visual inspection for son using a dissecting microscope. Representative images of a strain producing many sori (WS-517) and a strain producing few sori (WS-69) are shown in
Example 2
This example describes the use of a high throughput screening assay to identify Dicty strains from Alaska (e.g., BAC10A, BAF6A, BAC3A, NW2, KB4A (ATCC® MYA-4262™) SO8B, SO3A, BAF9B, IC2A (ATCC® MYA-4259™), AK1A1 (ATCC® MYA-4272™) PBF4B (ATCC® MYA-4263), PBF8B, BSB1A, SO5B (ATCC® MYA-4249), PBF3C, PBF6B, NW2B, NW10B (ATCC® MYA-4271™), PBF9A, IC5A (ATCC® MYA-4256TH), ABC8A (ATCC® MYA-4260), NW16B, ABC10B, ABB6B (ATCC® MYA-4261), BA4A (ATCC® MYA-4252), AKK5A, AKK52C, HP4 (ATCC® MYA-4286), HP8 (ATCC® MYA-4284), or NW9A) that feed on Dd and Pcc at 10° C. on potatoes.
Results from 11 Dicty strains screened against Dd at 10° C. are presented in
The Alaskan Dicty strains, and those identified in Example 1, are further tested against coinfections of Dd and Pcc. It is useful to identify Dicty strains that can suppress Dd and Pcc coinfections as these two pathogens have been isolated together from diseased potatoes (15). The ability of Dicty strains with different feeding preferences (Dd vs. Pcc) to complement each other when administered as a cotreatment is assayed.
Example 8
Administration of bleomycin, a DNA damaging agent, to the anterior chamber of the mouse or rabbit eye leads to cellular senescence, as detected by the induction of p16 transcript in the trabecular meshwork.
To induce a senescent phenotype in the trabecular meshwork in vivo, C57Bl/6 mice (aged 8 to 10 weeks) were injected intracamerally with 2 μL of 0.0075 U bleomycin sulfate. In the rabbit, 30 μL of 0.0075 U bleomycin sulfate were injected intracamerally in New Zealand white rabbits. Eyes were enucleated 14 days post-bleomycin injury and TM-enriched samples were micro-dissected. To determine change in senescent cells, RNA was isolated from TM and qPCR analysis was done to assess the effect of bleomycin on p16 mRNA levels.