Phenotypic Characterization and Molecular Mapping of anacaulis2Mutant ofArabidopsis thalianawith Flower Stalks of Much Reduced Length

摘要

Anacaulis2-1(acl2-1) mutant ofArabidopsis thaliana(L.) Heynh. was isolated and characterized. The mutant had inflorescences of much reduced length. The defect was severer in lower internodes and was visible preferentially in type 2 metamers. The defect in the elongation of internodal cells of inflorescences was attributable to a defect in the mechanism for elongation of these cells. The cortical microtubules (MTs) were analyzed in theacl2mutant, in a comparison with those of anacl1mutant which was described earlier, but no changes were detected in amounts of MTs. In the type 2 and type 3 metamers, the defect in elongation inaclmutants was loosely correlated with a change in the orientation of MTs. Thus, the abnormal arrangement of MTs appears to be one of the pleiotropic effects ofacaulismutations.Genetic mapping was performed using molecular markers and theACL2gene was located at 100 map units on chromosome 1.