Isolation, Characterization and Expression Analysis of Stearoyl-ACP Desaturase Gene from Kosteletzkya virginica

Kosteletzkya virginica is a halophyte species which could be used for production of industrial raw material such as biodiesel and for developing ecologically sound saline agriculture as well as for tideland soil improving. Using Rapid Amplification of cDNA Ends (RACE) method, a 1610 bp cDNA of stearoyl-ACP desaturase (SAD) gene containing a 1188 bp complete open reading fragment (ORF) was firstly isolated from seeds of K. virginica. Sequence analysis revealed that the nucleotide sequence of K. virginica SAD had a high level of homology to SAD from Gossypium hirsutum, but had relative low identity to SAD from other pants. However, K. virginica SAD had a high level of amino acid sequence homology to SAD from other plants. Characteristics of the deduced protein were predicted and analyzed using bioinformatic methods. Expression analysis via real-time PCR indicated that expression levels of the SAD gene were markedly distinct in different K. virginica tissues and different development stage seeds. The results of the expression analysis in this study, combined with existing research, suggest that SAD may be involved in the regulation of plant seed growth and development. These results serve as a foundation for further studies of the mechanisms regulating SAD gene expression and could eventually lead to the development of higher quality K. virginica varieties.