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PubMed · 2753045

Crystallin gene expression during rat lens development.

H J Aarts·N H Lubsen·J G Schoenmakers
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Abstract

The analysis of the developmental pattern of the alpha A-, alpha B-, beta B1-, beta B2-, beta B3-, beta A3/A1-, and beta s-crystallin genes during fetal and postnatal development of the rat shows that the differential regulation of crystallin synthesis relies on differential gene shutdown rather than differential gene activation; that is, all crystallin genes are active during early development but turn off at different stages. The only two exceptions to this rule are the alpha B- and beta s-crystallin genes. The alpha B-crystallin gene transcript becomes first detectable at 18 days of fetal development, while the beta s-crystallin gene appears to be active only in the postnatal period. We also determined the absolute numbers of the alpha A-, alpha B-, beta B1-, beta B2-, beta B3-, beta A3/A1-, beta s-, and gamma-crystallin gene transcripts present in the lens at various times after birth. Comparison of these RNA data with the published protein data shows that the alpha B- and beta B2-crystallin RNAs are relatively overrepresented, suggesting the possibility that these two RNA species are not used as efficiently as other crystallin mRNAs. Examination of the known (hamster) alpha B-crystallin sequence and elucidation of the (rat) beta B2-crystallin sequence yielded no evidence for aberrant codon usage. These two RNAs have one sequence motif in common: they are the only crystallin mRNAs in which the translation initiation codon is preceded by CCACC.

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Age FactorsAmino Acid SequenceAnimalsBase SequenceBlotting, NorthernBlotting, SouthernCrystallinsDNALens, CrystallineMolecular Sequence DataProtein BiosynthesisRNA, MessengerRatsSequence Homology, Nucleic AcidTranscription, GeneticComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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H J Aarts, N H Lubsen, J G Schoenmakers. 1989-07-15. Crystallin gene expression during rat lens development.. https://doi.org/10.1111/j.1432-1033.1989.tb14892.x

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