Characterization of a cDNA clone encoding molluscan insulin-related peptide V of Lymnaea stagnalis.
A cDNA clone encoding molluscan insulin-related peptide V (MIP V) was isolated from a cDNA library of the central nervous system (CNS) of the freshwater snail, Lymnaea stagnalis, using a heterologous screening with a previously identified MIP II cDNA. The MIP V cDNA encodes a preprohormone resembling the organization of preproinsulin, with a putative signal sequence, and an A and B chain, however, in this case connected by two distinct C peptide, C alpha and C beta, instead of one single C peptide. This phenomenon, which is shared by the MIP II precursor, represents a new development in the prohormone organization of peptides belonging to the insulin superfamily. The A and B chains of MIPs V, I and II, differ remarkably in primary structure; in contrast, the C alpha peptide domains are almost identical. MIP V has only limited sequence similarity with insulins and related peptides. Both MIP V and I exhibit structural features, which make them a unique class of the insulin superfamily. The MIP I, II and V genes are expressed in a single type of neuron: the growth controlling neuroendocrine light green cells of the Lymnaea CNS.
Smit
A B
AB
Department of Biology, Vrije Universiteit, Amsterdam, The Netherlands.
Thijsen
S F
SF
Geraerts
W P
WP
Meester
I
I
van Heerikhuizen
H
H
Joosse
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics*; D005796:Genes; D007448:Invertebrates / Q000235:genetics; D008195:Lymnaea / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009479:Neuropeptides / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D014714:Vertebrates / Q000235:genetics
D009479:Neuropeptides; D011498:Protein Precursors; C063879:insulin-related neuropeptide; D004247:DNA