Abstract: The fem-1 gene plays a key role in sex determination in Caenorhabditis elegans. In this study, three homologs of the C. elegans fem-1 gene were cloned and characterized from a transcriptome database of the oriental migratory locust, Locusta migratoria manilensis, based on bioinformatical analysis. They were named Lmfem-1a, Lmfem-1b and Lmfem-1c, with the Genbank accession numbers of AB698670, AB698671 and AB698672, respectively. The cDNAs of the three genes are 2 233, 2 625 and 2 142 bp in length, encoding proteins with 662, 642 and 638 amino acids, respectively. Bioinformatical analysis revealed that Lmfem-1a, Lmfem-1b and Lmfem-1c contain 6, 8 and 8 typical ankyrin repeat motifs, respectively. Gene expression analysis showed that Lmfem-1a, Lmfem-1b and Lmfem-1c were expressed in all tested tissues with significantly different transcript level, suggesting that Lmfem-1a, Lmfem-1b and Lmfem-1c are tightly regulated and might be involved in multiple physiological processes. Lmfem-1a, Lmfem-1b and Lmfem-1c had the highest expression level in testis, and their expression increased gradually with the development of testis. These findings strongly suggest that Lmfem-1a, Lmfem-1b and Lmfem-1c may be involved in the spermatogenesis of the locust. Further functional analysis is required to clarify the roles of these genes in sex determination in the locust.

Key words: Locusta migratoria manilensis, fem-1 gene, homologs, cloning, bioinformatical analysis, expression profile, quantitative real-time PCR