Open Accessɛ‐Crystallin, a novel avian and reptilian eye lens protein
Author(s) -
STAPEL Steven O.,
ZWEERS Anneke,
DODEMONT Huub J.,
KAN Jaap H.,
JONG Wilfried W.
Publication year - 1985
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1985.tb08728.x
Subject(s) - crystallin , eye lens , lens (geology) , size exclusion chromatography , biology , crystallography , chemistry , genetics , microbiology and biotechnology , biochemistry , enzyme , paleontology
Gel filtration of Peking duck eye lens proteins reveals a component eluting just behind δ‐crystallin and comprising approximately 10% of the total soluble protein. The native M r of this additional component is estimated to be 120000; it appears to be composed of three identical chains of M r 38000 and pl 7.5. Circular dichroic spectroscopy showed a relatively high α‐helical content. No immunological cross‐reactivity is found with α‐, β‐, γ‐ or δ‐crystallins, and partial amino acid sequence determinations likewise failed to reveal any similarity with other known crystallins. We conclude that this protein represents another and novel family of eye lens proteins, for which we propose the designation ɛ‐crystallin. ɛ‐Crystallin is translated from a 1450‐base mRNA, which has been partially purified. ɛ‐Crystallin is found scattered among avian and reptilian taxa, but not in other vertebrates. Its rate of evolutionary change seems to be as slow as that of α‐ and β‐crystallins.