Abstract
In apparent contrast to most other tissues, the ocular lenses in vertebrates show striking differences in protein composition between taxa, most notably in the recruitment of different enzymes as major structural proteins. This variability appears to be the result of at least partially neutral evolutionary processes, although there is also evidence for selective modification in molecular structure. Here we describe a bird, the chimney swift (Chaetura pelagica), that lacks delta-crystallin/argininosuccinate lyase, usually the major crystallin of avian lenses. Clearly, delta-crystallin is not specifically required for a functionally effective avian lens. Furthermore the lens composition of the swift is more similar to that of the related hummingbirds than to that of the barn swallow (Hirundo rustica), suggesting that phylogeny is more important than environmental selection in the recruitment of crystallins. However differences in epsilon-crystallin/lactate dehydrogenase-B sequence between swift and hummingbird and other avian and reptilian species suggest that selective pressures may also be working at the molecular level. These differences also confirm the close relationship between swifts and hummingbirds.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Hejtmancik J. F., Thompson M. A., Wistow G., Piatigorsky J. cDNA and deduced protein sequence for the beta B1-crystallin polypeptide of the chicken lens. Conservation of the PAPA sequence. J Biol Chem. 1986 Jan 15;261(2):982–987. [PubMed] [Google Scholar]
- Hendriks W., Mulders J. W., Bibby M. A., Slingsby C., Bloemendal H., de Jong W. W. Duck lens epsilon-crystallin and lactate dehydrogenase B4 are identical: a single-copy gene product with two distinct functions. Proc Natl Acad Sci U S A. 1988 Oct;85(19):7114–7118. doi: 10.1073/pnas.85.19.7114. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kiltz H. H., Keil W., Griesbach M., Petry K., Meyer H. The primary structure of porcine lactate dehydrogenase: isoenzymes M4 and H4. Hoppe Seylers Z Physiol Chem. 1977 Jan;358(1):123–127. doi: 10.1515/bchm2.1977.358.1.123. [DOI] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Milstone L. M., Piatigorsky J. Rates of protein synthesis in explanted embryonic chick lens epithelia: differential stimulation of delta-crystallin synthesis. Dev Biol. 1975 Mar;43(1):91–100. doi: 10.1016/0012-1606(75)90133-5. [DOI] [PubMed] [Google Scholar]
- Piatigorsky J. Delta crystallins and their nucleic acids. Mol Cell Biochem. 1984;59(1-2):33–56. doi: 10.1007/BF00231304. [DOI] [PubMed] [Google Scholar]
- Piatigorsky J., Norman B., Jones R. E. Conservation of delta-crystallin gene structure between ducks and chickens. J Mol Evol. 1987;25(4):308–317. doi: 10.1007/BF02603115. [DOI] [PubMed] [Google Scholar]
- Piatigorsky J., O'Brien W. E., Norman B. L., Kalumuck K., Wistow G. J., Borras T., Nickerson J. M., Wawrousek E. F. Gene sharing by delta-crystallin and argininosuccinate lyase. Proc Natl Acad Sci U S A. 1988 May;85(10):3479–3483. doi: 10.1073/pnas.85.10.3479. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Piatigorsky J., Wistow G. J. Enzyme/crystallins: gene sharing as an evolutionary strategy. Cell. 1989 Apr 21;57(2):197–199. doi: 10.1016/0092-8674(89)90956-2. [DOI] [PubMed] [Google Scholar]
- Stapel S. O., Zweers A., Dodemont H. J., Kan J. H., de Jong W. W. epsilon-Crystallin, a novel avian and reptilian eye lens protein. Eur J Biochem. 1985 Feb 15;147(1):129–136. doi: 10.1111/j.1432-1033.1985.tb08728.x. [DOI] [PubMed] [Google Scholar]
- Stapel S. O., de Jong W. W. Lamprey 48-kDa lens protein represents a novel class of crystallins. FEBS Lett. 1983 Oct 17;162(2):305–309. doi: 10.1016/0014-5793(83)80777-7. [DOI] [PubMed] [Google Scholar]
- Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wawrousek E. F., Nickerson J. M., Piatigorsky J. Two delta-crystallin polypeptides are derived from a cloned delta 1-crystallin cDNA. FEBS Lett. 1986 Sep 15;205(2):235–240. doi: 10.1016/0014-5793(86)80904-8. [DOI] [PubMed] [Google Scholar]
- Wistow G. J., Lietman T., Williams L. A., Stapel S. O., de Jong W. W., Horwitz J., Piatigorsky J. Tau-crystallin/alpha-enolase: one gene encodes both an enzyme and a lens structural protein. J Cell Biol. 1988 Dec;107(6 Pt 2):2729–2736. doi: 10.1083/jcb.107.6.2729. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wistow G. J., Mulders J. W., de Jong W. W. The enzyme lactate dehydrogenase as a structural protein in avian and crocodilian lenses. Nature. 1987 Apr 9;326(6113):622–624. doi: 10.1038/326622a0. [DOI] [PubMed] [Google Scholar]
- Wistow G. J., Piatigorsky J. Lens crystallins: the evolution and expression of proteins for a highly specialized tissue. Annu Rev Biochem. 1988;57:479–504. doi: 10.1146/annurev.bi.57.070188.002403. [DOI] [PubMed] [Google Scholar]
- Wistow G., Piatigorsky J. Recruitment of enzymes as lens structural proteins. Science. 1987 Jun 19;236(4808):1554–1556. doi: 10.1126/science.3589669. [DOI] [PubMed] [Google Scholar]
- Wistow G., Turnell B., Summers L., Slingsby C., Moss D., Miller L., Lindley P., Blundell T. X-ray analysis of the eye lens protein gamma-II crystallin at 1.9 A resolution. J Mol Biol. 1983 Oct 15;170(1):175–202. doi: 10.1016/s0022-2836(83)80232-0. [DOI] [PubMed] [Google Scholar]