Author/Editor		Lenasi, Valentina
Title		Izolacija in karakterizacija cDNA za kazeine pri konju (E. caballus)
Translated title		Isolation and characterization of cDNA for equine caseins (E. caballus)
Type		monografija
Place		Domžale
Publisher		Medicinska fakulteta
Publication year		2001
Volume		str. 72
Language		slo
Abstract		Caseins comprise about 50% of the total milk proteins in mare milk and their most important role is providing the major supply of amino acids, calcium and phosphorus to the suckling foal. Connected via hydrophobic interactions and disulphide bonds in milk they form loosely ordered aggregates, termed casein micelles. They can be divided into two classes, so called calcium-sensitive casein (as1-, as2- and B-casein) and k-casein. The important role of k-casein is in determining the micelle structure and maintaining the calcium-sensitive caseins in suspension. In addition, k-casein is responsible for clotting of milk in the gut. Calcium-sensitive casein bind calcium phosphate via phosphorylated amino acids, increasing calcium and phosphate concentrations in milk. Most of the research has been done on bovine casein genes, followed by casein genes of some other dairy species. The aim of our work was to isolate and characterize equine casein mRNAs because of the possible use of mares milk for children with cows milk allergy. This allergy is caused by certain proteins in cows milk, therefore we wanted to compare equine casein genes with human and bovine casein counterparts. Sintesizing DNA probes for individual caseins, preparing and screening equine mammary gland cDNA library we searched for recombinant clones, containing casein cDNA inserts. We isolated cDNA for equine as1-, B- and k-casein and determined sequences of the coding regions, the 3 entire noncoding and most of the 5 noncoding regions. For as1- casein we obtained two mRNAs, differing in lenght for 33 nucleotides. We deduced from sequences that both mRNAs are processed from the same pre-mRNA and that the shorter mRNA probably lacks the whole exon, which is skipped during the splicing process. Analysis of the sequences showed higher sequence identity of equine and human casein mRNAs then of corresponding human and bovine mRNAs. (Abstract truncated at 2000 characters).
Descriptors		CASEINS RNA, MESSENGER DNA PROBES GENE LIBRARY SEQUENCE ANALYSIS, DNA HORSES SEQUENCE ANALYSIS, RNA MILK PLASMIDS BASE SEQUENCE TRANSFORMATION, GENETIC DNA, RECOMBINANT AMINO ACID SEQUENCE