Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-2-8
pubmed:abstractText
Proteins in pupal abdominal cuticle of the tobacco hornworm, Manduca sexta, were characterized during the pre-ecdysial and post-ecdysial periods of sclerotization and endocuticle formation. Protein extractability decreased dramatically as the cuticle became sclerotized through 6 h post-ecdysis, but increased rapidly from 9 to 48 h as endocuticular layers were secreted. Nearly 100 proteins that were extracted from pre-ecdysial cuticle became largely insoluble during sclerotization. Three major proteins in this group destined to become exocuticle had apparent molecular masses (Mapp) of 20, 27 and 36 kDa, and were designated MS-PCP20, MS-PCP27, and MS-PCP36. Amino acid analysis revealed glycine to predominate in all three proteins, and alanine, aspartate, glutamate, proline and serine were also relatively abundant. Histidine residues, which provide sites for adduct and cross-link formation with quinone metabolites of N-beta-alanyldopamine during sclerotization of pupal cuticle, ranged from 2 to 3 mol %. N-Terminal amino acid analysis of MSPC-20 and MSPC-36 also revealed some sequence similarities indicating they may be related. An almost entirely new group of proteins appeared by 9 h as endocuticule secretion began, and these increased in abundance through 48 h post-ecdysis. Two of these were major proteins with Mapps of 33 and 34 kDa, and they also had close similarities in their N-terminal amino acid sequences. This study showed that the large number of proteins secreted into the presumptive exocuticle of the pupa before ecdysis are involved in sclerotization reactions and as a consequence become largely insoluble. The epidermis then switches to the secretion of an entirely new group of proteins that are involved in formation of the endocuticle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0965-1748
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
19-27
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Pupal cuticle proteins of Manduca sexta: characterization and profiles during sclerotization.
pubmed:affiliation
Department of Entomology, Kansas State University, Manhattan 66506-4004, USA. thopkins@oz.oznet.ksu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't