'''Lustrin A''' is an insoluble protein used in the production of a nacreous layer in bivalve molluscs.<ref name="ReferenceA">{{Cite journal| doi = 10.1074/jbc.272.51.32472| title = Molecular Cloning and Characterization of Lustrin A, a Matrix Protein from Shell and Pearl Nacre of Haliotis rufescens| year = 1997| last1 = Shen | first1 = X.| journal = Journal of Biological Chemistry| volume = 272| pages = 32472–81| last2 = Belcher | first2 = A. M.| last3 = Hansma | first3 = P. K.| last4 = Stucky | first4 = G. D.| last5 = Morse | first5 = D. E.| pmid = 9405458| issue = 51 | doi-access = free}}</ref> It contributes to the properties of the nacreous layer, imparting resistance to cracking and elasticity.<ref>{{Cite journal | first6 = B.| last6 = Degnan | first5 = G.| last5 = Wörheide| title = A rapidly evolving secretome builds and patterns a sea shell| volume = 4| journal = BMC Biology| pmc = 1676022| pages = 40 | first4 = F.| last4 = Simpson| last1 = Jackson| year = 2006| pmid = 17121673 | first1 = D.| last2 = McDougall | first3 = K.| last3 = Green | first2 = C.| doi = 10.1186/1741-7007-4-40 | doi-access = free }}</ref> This is accomplished by its structure; it consists of many spring-like units which can expand when the shell is under extensional pressure.<ref name=Marin2004>{{Cite journal| doi = 10.1016/j.crpv.2004.07.009| title = Molluscan shell proteins| year = 2004| last1 = Marin | first1 = F.| last2 = Luquet | first2 = G.| journal = Comptes Rendus Palevol| volume = 3| issue = 6–7| pages = 469–492 }}</ref> Its structure is similar to that of proteins involved in ''silica'' deposition in diatoms.<ref name="ReferenceA"/> It consists of 1428 amino acid residues. Its molecular weight is estimated to be 142 kDa. Its terminus consists of a protease inhibitor, which contributes to its longevity in the molluscan shell matrix.<ref name=Marin2004/>
==References== {{Reflist}}
Category:Molluscan proteins