Complete nucleotide sequence of a cDNA derived from calf lens gamma-crystallin mRNA: presence of Alu I-like DNA sequences.

The nucleotide sequence of a cloned cDNA derived from gamma-crystallin mRNA of calf lens was determined. The cloned cDNA contains the entire coding region 522 bp long, 30 nucleotides of the 5' noncoding region, and 67 residues in the 3' noncoding region followed by a poly(A) tail of 25 nucleotides. The deduced amino acid sequence directly demonstrates for the first time that the calf gamma-crystallin contains 174 residues. The nucleotide sequence contains a number of interesting features including a 32-bp sequence in the 3' region with 70% complementarity to the 3' end of the first monomer unit of the consensus Alu I DNA. Within this region, a 32-bp sequence shows about 80% homology with a segment of hamster 4.5S RNA. The possible evolutionary and regulatory significance of these sequences is discussed.