Structure, processing and midgut secretion of putative peritrophic membrane ancillary protein (PMAP) from Tenebrio molitor larvae

Insect Biochemistry and Molecular Biology
A H P FerreiraClélia Ferreira

Abstract

A cDNA coding for a Tenebrio molitor midgut protein named peritrophic membrane ancillary protein (PMAP) was cloned and sequenced. The complete cDNA codes for a protein of 595 amino acids with six insect-allergen-related-repeats that may be grouped in A (predicted globular)- and B (predicted nonglobular)-types forming an ABABAB structure. The PMAP-cDNA was expressed in Pichia pastoris and the recombinant protein (64kDa) was purified to homogeneity and used to raise antibodies in rabbits. The specific antibody detected PMAP peptides (22kDa) in the anterior and middle midgut tissue, luminal contents, peritrophic membrane and feces. These peptides derive from PMAP, as supported by mass spectrometry, and resemble those formed by the in vitro action of trypsin on recombinant PMAP. Both in vitro and in vivo PMAP processing seem to occur by attack of trypsin to susceptible bonds in the coils predicted to link AB pairs, thus releasing the putative functional AB structures. The AB-domain structure of PMAP is found in homologous proteins from several insect orders, except lepidopterans that have the apparently derived protein known as nitrile-specifier protein. Immunocytolocalization shows that PMAP is secreted by exocytosis and becomes e...Continue Reading

References

Sep 1, 1979·Proceedings of the National Academy of Sciences of the United States of America·H TowbinJ Gordon
Oct 1, 1985·Analytical Biochemistry·P K SmithD C Klenk
Nov 7, 1998·The Journal of Biological Chemistry·A PomésM D Chapman
May 29, 2001·Archives of Insect Biochemistry and Physiology·W R Terra
May 29, 2001·Archives of Insect Biochemistry and Physiology·P Wang, R R Granados
May 31, 2002·Cell and Tissue Research·Lars Zimoch, Hans Merzendorfer
Mar 31, 2004·Proceedings of the National Academy of Sciences of the United States of America·Ute WittstockHeiko Vogel
Jan 25, 2006·Insect Biochemistry and Molecular Biology·A R LopesW R Terra
Jul 25, 2006·Comparative Biochemistry and Physiology. Part B, Biochemistry & Molecular Biology·K S VinokurovM A Belozersky

❮ Previous
Next ❯

Citations

Dec 11, 2008·Annual Review of Entomology·Dwayne HegedusUmut Toprak
Oct 16, 2012·Molecular Biology Reports·Xiaolong HuXiaofeng Wu

❮ Previous
Next ❯

Related Concepts

Related Feeds

Cajal Bodies & Gems

Cajal bodies or coiled bodies are dense foci of coilin protein. Gemini of Cajal bodies, or gems, are microscopically similar to Cajal bodies. It is believed that Cajal bodies play important roles in RNA processing while gems assist the Cajal bodies. Find the latest research on Cajal bodies and gems here.