Molecular cloning and characterization of a cDNA encoding a novel cuticle protein in the silkworm, Bombyx mori

• Published in: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 2003-03, Vol.134 (3), p.519-527
• Main Authors: Sawada, Hiroshi, Nakato, Hiroshi, Togawa, Toru, Nakagoshi, Motoko, Takikawa, Shin-Ichiro, Dohke, Kenjiro, Iino, Teruhiko, Mase, Keisuke, Yamamoto, Toshio, Izumi, Susumu
• Format: Article
• Language: English
• Subjects: Alanine–alanine–proline/valine-repeat; Amino Acid Sequence; Animals; Base Sequence; Blotting, Northern; Bombyx - genetics; Bombyx mori; cDNA cloning; Cloning, Molecular; Conserved Sequence; Cuticle protein; DNA, Complementary - chemistry; DNA, Complementary - genetics; Evolution, Molecular; Female; Gene Expression; Gene Library; Insect Proteins - genetics; Insect Proteins - metabolism; Male; Molecular Sequence Data; Primary structure; R&R consensus; Reverse Transcriptase Polymerase Chain Reaction; RNA polymerase II; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Amino Acid
• ISSN: 1096-4959; 1879-1107
• DOI: 10.1016/S1096-4959(03)00002-2

We have cloned the full length of a novel cDNA named Bombyx mori cuticle protein that contains an AlaAlaProAla/Val-repeat (BMCPA) from a cDNA library of integument in the larval silkworm. Both a typical tandem repeat (A–A–P–A/V) for cuticle protein and a unique tandem repeat with Ser, Ala, Gly, Pro, Val, Tyr and Thr were observed in the predicted amino acid sequence of the cDNA encoding BMCPA. Approximately 80% of the amino acids in BMCPA were composed of Ser, Ala, Gly, Pro, Val and Tyr. Northern-hybridization analysis indicated that BMCPA mRNA is expressed only in the larval epidermis and that the expression pattern of the BMCPA gene in the developmental stage was observed mainly at the larval stage. We propose BMCPA may be a novel component of cuticle, and may play an important role in the integument of the larval silkworm.