Cloning and sequence analysis of apomixis related gene MSI1 (Multicopy suppressor of ira1) in Taraxacum antungense

Abstract

Apomixis is a genetically determined type of asexual reproduction in angiosperms that results in the production of viable seed from maternal tissues in the absence of meiosis and fertilization. Apomicts reproduce clonally through seeds, including apomeiosis, parthenogenesis, and autonomous or pseudogamous endosperm formation. Apomixis is universal in Taraxacum sp.; however, some species have very high rate of apomixes. This study was conducted to clone gene(s) related with the apomixis in Taraxacum. Reproduction mode of Taraxacum antungense Kitag was obligate apomixis and of T. ohwianum Kitam was sexual reproduction. Overall length of MSI1 gene's cDNA of T. antungense was obtained utilizing the RACE (rapid amplification of cDNA ends). The cDNA is 1424 bp with an open reading frame of 1272 bp encoding 423 amino acids. The homology of MSI1 gene in T. antungense are high compare with other species, especially with the composite plants the homology with them are all more than 88%. Quantitative RT-PCR analysis showed that MSI1 gene is an apomixis related gene in Taraxacum and express at full-bloom flowering stage.