Mosquito vitellogenin subunits originate from a common precursor.
Using a cell-free translation system, we demonstrated that the two subunits of mosquito vitellogenin (VG), 200 kDa and 65 kDa, originate from a common precursor. The precursor polypeptide of 220 kDa is a translation product specific to mRNA from vitellogenic mosquitoes. In immunoprecipitation analysis, the 220-kDa polypeptide was recognized by monoclonal antibodies directed either to the large or the small VG subunit. Peptide mapping showed homology between the 220-kDa polypeptide and both subunits, thus providing further proof that the 220-kDa product of translation is the precursor for both VG subunits. In the presence of microsomal membranes, the molecular size of the VG precursor increased to 235 kDa suggesting this as a first step in co-translational modifications of VG.
Department of Entomology, Michigan State University, East Lansing 48824.
S G
SG
Bose
A S
AS
Raikhel
D000330:Aedes / Q000235:genetics*; D000818:Animals; D002474:Cell-Free System; D005216:Fat Body / Q000378:metabolism; D005260:Female; D008297:Male; D008970:Molecular Weight; D011498:Protein Precursors / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification; D011499:Protein Processing, Post-Translational; D012727:Sex Characteristics; D014819:Vitellogenins / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification
D011498:Protein Precursors; D014819:Vitellogenins