%A WANG Xiao-Juan,PAN Zhen-Yuan,LIU Min,LIU Zhong-Xiang,ZHOU Yu-Qian,HE Hai-Jun,QIU Fa-Zhan %T Genetic analysis and molecular characterization of a new allelic mutant of silky1 gene in maize %0 Journal Article %D 2019 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2019.93009 %P 1649-1655 %V 45 %N 11 %U {https://zwxb.chinacrops.org/CN/abstract/article_6765.shtml} %8 2019-11-12 %X

We identified a new maize male sterile mutant in early experiment, designated as msm-6. This mutant characters were steadily inherited and genetically regulated by a single recessive gene. An F2 population was developed by crossing B73 inbred line to msm-6, and four SSR markers (C6-24, C6-30, C6-34, and C6-40) closely linked to this locus were identified by BSA (Bulked Segregant Analysis) method. The 444 F2 individuals were used to map the target gene in an interval from 68.5 to 98.1 Mb between markers C6-24 and C6-34 on chromosome 6. Using genomic sequence database, we found that male sterile mutant gene Silky1 was located in this mapping region. Silky1 encodes a B function MADS box protein of ABCD model for floral organ establishment. The mutation of Silky1 led to sterile stamen and more silks of the ear. By crossing heterozygous +/silky1-mum3 plants to homozygous msm-6/msm-6 plants, we found a 1:1 segregation ratio for normal to male sterile plants. Genomic and cDNA sequences of msm-6 disclosed a single-nucleotide change from G to C at the first position of intron 6, which resulted in exon 6 skipping, producing aberrant mRNAs without exon 6. So msm-6 is a new allele mutant of Silky1, which is different from silky1-mum2, silky1-mum3, and silky1-mum4 caused by the insertion of mutator transposons. The identification of msm-6 provides not only abundant experimental materials for the study of the floral organ determination in maize, but also important evidence for the conservation of splicing sites in RNA processing.