Isolation, characterization and complete nucleotide sequence of a Galleria mellonella cDNA coding for the follicle cell-specific yolk protein, YP4.
An ovariole-specific yolk polypeptide cDNA from Galleria mellonella was isolated from a cDNA library constructed using vitellogenic ovariole poly (A)+ RNA, by differential screening with the ovariole and day-0 male pupal poly (A)+ RNA. The Ov11 cDNA hybridized to a 1.1 kb message from the ovariole but not from male pharate adults, ovariectomized pharate adults or day-5 last instar larvae. Developmental Northern analysis showed that this message is expressed only during vitellogenic stages. In situ hybridization of digoxigenin-dUTP labeled Ov11 cDNA to the day-8 pharate adult ovariole showed that only follicle cells express the Ov11 gene. The 960 bp Ov11 cDNA is nearly full-length, containing a single open reading frame coding for a 286 amino acid polypeptide with a hydrophobic signal sequence and two potential N-glycosylation and tyrosine sulfation sites. The fact that Ov11 cDNA codes for the 37 kDa ovariole-specific yolk protein, YP4, was confirmed by the N-terminal amino acid sequence analysis of purified YP4. Genomic Southern analysis suggests that the yp4 gene is a single copy gene and PCR analysis using the 5' and 3' end primers of the cDNA indicates that the yp4 gene is intronless within the coding region.
Rajaratnam
V S
VS
Department of Biology, Marquette University, Milwaukee, WI 53233, USA.
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D018076:DNA, Complementary; D004527:Egg Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D018628:Gene Dosage; D019476:Insect Proteins; D007438:Introns; D008297:Male; D008969:Molecular Sequence Data; D009036:Moths / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D004527:Egg Proteins; D019476:Insect Proteins; C104397:YP4 protein, insect