Characterization of the SCP/TAPS gene family in Drosophila melanogaster

• Published in: Insect biochemistry and molecular biology 2005-08, Vol.35 (8), p.825-835
• Main Authors: Kovalick, Gae E., Griffin, Donna L.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; Animals; Biological Evolution; conserved sequences; Cysteine-rich secretory proteins; Drosophila melanogaster; Drosophila melanogaster - genetics; Female; Gene evolution; Gene expression; Gene Expression Profiling; Gene Expression Regulation; insect proteins; introns; Male; Male reproduction; males; Molecular Sequence Data; multigene family; nucleotide sequences; Pathogenesis-related proteins; phylogeny; Reverse Transcriptase Polymerase Chain Reaction; SCP-like extracellular proteins; Seminal Plasma Proteins - analysis; Seminal Plasma Proteins - biosynthesis; Seminal Plasma Proteins - genetics; sequence analysis; sequence homology; Testis - physiology
• ISSN: 0965-1748; 1879-0240
• DOI: 10.1016/j.ibmb.2005.03.003

The SCP/Tpx-1/Ag5/PR-1/Sc7 (SCP/TAPS) gene family encodes proteins found in many eukaryotes. SCP/TAPS proteins are defined by the presence of an SCP/TAPS domain, and many participate in important physiological processes. Five SCP/TAPS genes were previously identified in Drosophila melanogaster and are expressed in the digestive tract or in the testes. Sequence databases were searched to determine if other SCP/TAPS genes were present in D. melanogaster, and an additional 21 SCP/TAPS genes were identified. To further define the roles of these genes, the structures of each gene and protein were analyzed. Based on these analyses, 25 SCP/TAPS genes could be placed into one of two groups. Each group contained conserved intron positions that were not shared with the other group. Proteins encoded by group 1 genes also shared additional sequence motifs and conserved cysteines not found in group 2 proteins. To determine if the two groups were expressed differently, reverse transcriptase (RT)-polymerase chain reaction (PCR) was used to examine expression in adult flies. The results indicated that most genes were preferentially expressed in adult males, suggesting a role for these genes in male reproduction. Members of both groups displayed this preferential expression, so it was not group-specific. The two groups may differ in localization rather than function.