Identification, sequence and mRNA expression pattern during metamorphosis of a cDNA encoding a glycine-rich cuticular protein in Tenebrio molitor.
The study of insect cuticular proteins and their sequences is of interest because they are involved in protein-protein and protein-chitin interactions which confer the mechanical properties and fine architecture of the cuticle. Moreover, in the coleopteran Tenebrio molitor there is a dramatic change in cuticular architecture between pre- and postecdysial secretion. We report the isolation, by differential screening, and the sequence characterization of a cDNA clone encoding a cuticular protein of T. molitor, ACP17. After insertion in the expression vector pEX1, the recognition of the fusion protein by an anti-cuticular monoclonal antibody confirmed the cuticular nature of ACP17. Northern hybridization analysis showed that ACP17 mRNA expression begins weakly 3 days before adult ecdysis and strongly increases during the secretion of postecdysial adult cuticle, with a maximum just after ecdysis. In situ hybridization revealed that the ACP17 mRNA is only present in the epidermis which secretes hard cuticle. The deduced amino acid (aa) composition exhibits a high content of Gly (28%) and Ala (20%) and, particularly, two poly(Gx) stretches separated by repetitive motifs with proline AAPVA. A comparison is made with other cuticle aa sequences.
Mathelin
J
J
Laboratoire de Zoologie, UA CNRS 674, Université de Bourgogne, Dijon, France.
Bouhin
H
H
Quennedey
B
B
Courrent
A
A
Delachambre
J
J
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015870:Gene Expression; D017403:In Situ Hybridization; D019476:Insect Proteins; D008675:Metamorphosis, Biological; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D017422:Sequence Analysis, DNA; D013712:Tenebrio / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development; D014018:Tissue Distribution
C112954:ACP17 protein, Tenebrio molitor; D019476:Insect Proteins; D011506:Proteins; D012333:RNA, Messenger; C047663:cuticle proteins, insects