ARS | Publication request: INVOLVEMENT OF CALLASE IN A NEW GENETIC MALE-STERILE SOYBEAN MUTANT

Submitted to: Botanical Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: April 17, 1997
Publication Date: N/A

Technical Abstract: At least three genes have been isolated that produce a male-sterile phenotype, but their gene products do not provide obvious clues as to the roles that these genes play during male cell development. This illustrates the complexities of male gametophyte development. Analyses of soybean mutants have identified at least seven genetic loci that, when disrupted, yield arrested or developmentally abnormal male cells. Some of these mutations affect the early stages of microsporogenesis. In a mutant obtained from Midwest Oil Seeds, in vitro enzyme studies showed no callase (beta-1,3-glucanase) activity in the male-sterile mutant anthers at the tetrad stage of microsporogenesis. These results, along with microscopic observations, suggest that male-sterility was caused by retention of the callose walls surrounding the tetrads. RNA level studies showed a reduction in callase mRNA in the mutant, as compared to the male fertile. But transcription occurred in both the mutant and fertile tapeta according to in situ hybridization studies. Protein level analyses are being conducted to determine if translation is affected in the mutant. Immunocytochemistry is being used to locate the site and time of beta-1,3- glucanase activity in the mutant and fertile anther tissues.