Cloning of potato SBgLR gene and its intron splicing in transgenic maize

Abstract

A SBgLR genomic clone was isolated from potato genomic library using SB401 cDNA as probe. The gene contains three exons, two introns and encodes a protein with lysine composition up to 18.93% (w/w). The two introns exhibit highly conserved GT/AG dinucleotides in both 5′ and 3′ splice site, and AT-richness, i.e. 71 and 67%, respectively. In order to investigate whether an intron of dicot origin can be spliced in monocot plant, the plant expression construct (19Z: SBgLR) was constructed and introduced into maize immature embryonic callus by microprojectile bombardment. RT-PCR analyses of transgenic plants revealed that splicing of the two introns was accurately and efficiently processed in maize. Western blot indicated SBgLR protein was expressed in transgenic maize seeds with more lysine and protein content than the transgenic maize harboring SB401 cDNA.