Summary
We have cloned a fibroin gene from the Japanese oak silkworm, Antheraea yamamai, which belongs to the Saturniidae. The cloned DNA covers the entire region of the fibroin gene and a 1.4 kb 5′flanking sequence. Structural analysis of the gene by restriction mapping, S1 digestion and primer extension experiments shows that of Bombyx mori; both genes consist of one intron near the 5′end and two exons. Sequence comparison between the two genes reveals that the first exon of about 70 bp and the sequence around the splicing junctions, is very well conserved between the two species, whereas there is no sequence homology in the core region encoding the main polypeptide sequence. Interestingly, the 5′flanking sequence of the A. yamamai fibroin gene at -300 to -20 is homologous with that of B. mori in many patches including the TATA box region. Furthermore, the Antheraea fibroin gene could be transcribed faithfully in a posterior silk gland extract from B. mori. From this evidence, we conclude that the DNA sequence and the mechanisms that are necessary for fibroin gene expression in the posterior silk gland cells are probably conserved in the two families, Bombyx and Antheraea.
Similar content being viewed by others
References
Breathnach R, Chambon P (1981) Organization and expression of eucaryotic split genes coding for proteins. Annu Rev Biochem 50:349–383
Couble P, Chevillard M, Moine A, Ravel-Chapuis P, Prudhomme JC (1985) Structural organization of the P25 gene of Bombyx mori and comparative analysis of its 5′flanking DNA with that of the fibroin gene. Nucleic Acids Res 13:1801–1814
Fraser RQB, MacRae TP (1973) Conformation in fibrous protein and related synthetic polypeptide, Academic Press, New York London
Gage LP, Manning RF (1980) Internal structure of the silk fibroin gene of Bombyx mori. 1. The fibroin gene consists of a homogeneous alternating array of repetitious crystalline and amorphous coding sequences. J Biol Chem 255:9444–9450
Greene RA, Morgan M, Shatkin AJ, Gage LP (1975) Translation of silk fibroin messenger RNA in an Ehrlich asites cell-free extract. J Biol Chem 250:5114–5121
Hirose S, Tsuda M, Suzuki Y (1985) Enhanced transcription of fibroin gene in vitro on covalently closed circular templates. J Biol Chem 260:10557–10562
Hohn B (1979) In vitro packaging of λ and cosmid DNA. Methods Enzymol 68:299–309
Hultmark D, Klemenz R, Gehring WJ (1986) Translational and transcriptional control elements in the untranslated leader of the heat-shock gene hsp22. Cell 44:429–438
Kirimura J (1962) Studies on amino acid composition and chemical structure of silk protein by microbiological determination. Bull Sericul Exp Sta 17:447–522
Kusuda J, Tazima Y, Onimaru K, Ninaki O, Suzuki Y (1986) The sequence around the 5′end of the fibroin gene from the wild silkworm, Bombyx mandarina, and comparison with that of the domesticated species, B. mori. Mol Gen Genet 203:359–364
Lucas F, Rudall KM (1968) Extracellular fibrous proteins: The silks. In: Florkin M, Stotz EH (eds) Comprehensive Biochemistry, vol 26B, Elsevier, Amsterdam, pp 475
Manning RF, Gage LP (1980) Internal structure of the silk fibroin gene of Bombyx mori. II. Remarkable polymorphism of the organization of crystalline and amorphous coding sequences. J Biol Chem 255:9451–9457
Maxam AM, Gilbert W (1977) A new method for sequencing DNA. Proc Natl Acad Sci USA 74:560–564
Ohshima Y, Suzuki Y (1977) Cloning of the silk fibroin gene and its flanking sequences. Proc Natl Acad Sci USA 74:5363–5367
Okamoto H, Ishikawa E, Suzuki Y (1982) Structural analysis of sericin genes. Homologies with fibroin gene in the 5′flanking nucleotide sequences. J Biol Chem 257:15192–15199
Sanger F, Nicklen S, Coulson SR (1977) DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci USA 74:5463–5467
Suzuki Y, Brown DD (1972) Isolation and identification of the messenger RNA for silk fibroin from Bombyx mori. J Mol Biol 63:409–429
Suzuki Y, Oshima Y (1978) Isolation and characterization of the silk fibroin gene with its flanking sequences. Cold Spring Harbor Symp Quant Biol 42:947–957
Suzuki Y, Tsuda M, Hirose S, Takiya S (1986a) Transcription signals and factors of the silk genes. Adv Biophys 21:205–215
Suzuki Y, Tsuda M, Takiya S, Hirose S, Suzuki E, Kameda M, Ninaki O (1986b) Tissue-specific transcription enhancement of the fibroin gene characterized by cell-free systems. Proc Natl Acad Sci USA 83:9522–9526
Tsuda M, Suzuki Y (1981) Faithful transcription initiation of fibroin gene in a homologous cell-free system reveals an enhancing effect of 5′flanking sequence far upstream. Cell 27:175–182
Tsuda M, Suzuki Y (1983) Transcription modulation in vitro of the fibroin gene exerted by a 200-base-pair region upstream from the “TATA” box. Proc Natl Acad Sci USA 80:7442–7446
Tsujimoto Y, Suzuki Y (1979a)_Structural analysis of the fibroin gene at the 5′end and its surrounding regions. Cell 16:425–436
Tsujimoto Y, Suzuki Y (1979b) The DNA sequence of Bombyx mori fibroin gene including the 5′flanking, mRNA coding, entire intervening and fibroin protein coding regions. Cell 18:591–600
Tsujimoto Y, Hirose S, Tsuda M, Suzuki Y (1981) Promotor sequence of fibroin gene assigned by in vitro transcription system. Proc Natl Acad Sci USA 78:4838–4842
Author information
Authors and Affiliations
Additional information
Communicated by M. Takanami
Rights and permissions
About this article
Cite this article
Tamura, T., Inoue, H. & Suzuki, Y. The fibroin genes of Antheraea yamamai and Bombyx mori are different in their core regions but reveal a striking sequence similarity in their 5′ ends and 5′flanking regions. Mol Gen Genet 207, 189–195 (1987). https://doi.org/10.1007/BF00331577
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00331577