Sequence polymorphism characteristics in the See2β gene from maize key inbred lines and derived lines in China

Research on the sequence polymorphism characteristics of key genes is important in the early identification of maize inbred lines. The See2β gene functions in remobilizing leaf nitrogen and exporting it to developing grain during foliar senescence. We analyzed See2β sequences from 49 inbred lines representing four key lines and their derivatives: Huangzaosi, Mo17, Dan340, and Ye478. We found that the See2β gene had one insertion and two deletions in most Huangzaosi lines and three insertions in the Mo17 group; that the Huangzaosi, Dan340, and Ye478 lines, but not the Mo17 line, had unique indels; and that the See2β gene in lines derived from the same key inbred line had higher sequence homology, according to phenetic analysis of the inbred lines derived from Huangzaosi and Mo17. Thus, a candidate inbred line could be preliminarily identified using markers closely linked to the See2β gene combined with sequence alignment of See2β.