Nucleotide sequence determination of guinea-pig casein B mRNA reveals homology with bovine and rat αs1 caseins and conservation of the non-coding regions of the mRNA.

Abstract

Nucleotide sequence analysis of cloned guinea-pig casein B cDNA sequences has identified two casein B variants related to the bovine and rat alpha s1 caseins. Amino acid homology was largely confined to the known bovine or predicted rat phosphorylation sites and within the 'signal' precursor sequence. Comparison of the deduced nucleotide sequence of the guinea-pig and rat alpha s1 casein mRNA species showed greater sequence conservation in the non-coding than in the coding regions, suggesting a functional and possibly regulatory role for the non-coding regions of casein mRNA. The results provide insight into the evolution of the casein genes, and raise questions as to the role of conserved nucleotide sequences within the non-coding regions of mRNA species.

Physiology and Biochemistry of Lactation

“…With the aid of these techniques attention has also widened to include caseins and whey proteins of the cow Brew, 1972;Ribadeau-Dumas et al, 1972;Grosclaude et al, 1973;Brignon et al, 1977), sheep Oolles et al, 1974;Richardson and Mercier, 1979), goat (MacGillivray et al, 1979;Preaux et al, 1979), deer (McDougall and Stewart, 1976), horse (Visser et al, 1982), rabbit (Hopp and Woods, 1979;Dayal et al, 1982), guinea pig (Hall et al, 1984a(Hall et al, , 1984b, rat (Brown et al, 1977;Hirose et al, 1981;Blackburn et al, 1982;Qasba and Safaya, 1984), mouse (Kinkade et al, 1976;Hennighausen et al, 1982a,b), human (Findlay and Brew, 1972;Metz-Boutigue et al, 1984) and other species. References to j3-lactoglobulin biosynthesis in various species may be found in Godovac-Zimmerman and Braunitzer (1987).…”

Molecular characterization and in-vitro hormonal requirements for expression of two casein genes from a marsupial

“…The signal peptide of both tammar caseins com¬ prises 15 amino acid residues, a characteristic of the eutherian caseins (Hall, Laird & Craig, 1984;Bons¬ ing & Mackinlay, 1987). The open-reading frames of the tammar ß-casein and a-casein cDNAs code for mature proteins of 287 (Mr=34 291) and 222 (MT = 2b 503) amino acids respectively.…”

The sequence of porcine αs1‐casein cDNA: evidence for protein variants generated by altered RNA splicing

“…Based on comparison with the bovine aSl-casein the porcine cDNA encodes a mature protein of 191aa (M, 24,273; non-phosphorylated form) and a leader peptide of 15 aa. Sequence similarity of the leader peptide ranged from 71.1% [66.7%], in guinea pig casein B (Hall et al 1984), to 84.4% [80.0%] in the bovine (Stewart et al 1984) peptide. The overall similarity at the nucleotide level, and amino acid level [in brackets], to other species Figure 2.…”

“…The leader peptide sequence is well conserved between species. Sequence similarity of the leader peptide ranged from 71.1% [66.7%], in guinea pig casein B (Hall et al 1984), to 84.4% [80.0%] in the bovine (Stewart et al 1984) peptide.…”