Jm. Lee et al., Vitellogenin of the cicada Graptopsaltria nigrofuscata (Homoptera): analysis of its primary structure, INSEC BIO M, 30(1), 2000, pp. 1-7
We cloned and sequenced the cDNA of vitellogenin (Vg) from the cicada Grapt
opsaltria nigrofuscata (Homoptera).(1) The deduced amino acid sequence of 1
987 residues (including 16 residues for a putative signal peptide) was obta
ined. The pro-Vg was cleaved into two subunits between residues 379 and 380
following a consensus RXXR cleavage site sequence, secreted as S-Vg (appar
ent molecular weight 43 kDa) and L-Vg (200 kDa), sequestered, and stored in
the egg as two vitellins (Vns), S-Vn and L-Vn, with similar respective mol
ecular weights. There was a single long serine-rich stretch closely followi
ng the cleavage site. The entire amino acid sequences of the Vgs from the e
ight insects so far reported could be aligned confidently. The presence of
subdomains I-V (areas of relatively high amino acid conservation) and of 10
cysteines at conserved locations at the C-terminus, noted previously among
insect Vgs, were confirmed.
Antisera raised against G. nigrofuscata S- and L-Vn cross-reacted with the
S- and L-Vg/Nn, respectively, of all three other cicada species examined. A
nother major egg protein (170 kDa) unrelated to Vg/Vn, was also detected in
all species examined. (C) 2000 Elsevier Science Ltd. All rights reserved.