Map-based cloning of crinkle, which is required for infection thread development

Abstract

The nodulation mutant crinkle (crk) was identified from the model legume Lotus japonicus, which shows abortion of infection thread development between the junction of epidermis and cortex. The mutant shows defects in development of trichome, root hair, as well as pollen tube. We have recently identified that the male sterility is caused by the improper maturation of microspore, possibly caused by abortion in tapetum vacuolation. We regard crk is important for polar growth in general, and intend to clone the gene by map-based strategy. Initially crk locus was mapped in the middle of the linkage group 5, between TM0151 and TM0024. From these markers, TAC/BAC contigs were generated, and by the F2 population of 838 individuals, we narrowed down the candidate region into roughly 500kb.