High impact information on CSN3

• Single nucleotide polymorphisms (SNPs) within Bov-A2 SINE in the second intron of bovine and buffalo k-casein (CSN3) gene [1].
• With respect to the proteins, which they are derived off these peptides have been named alpha-casein exorphins or casoxin D (alpha-casein), beta-casomorphins or beta-casorphin (beta-casein), casoxin or casoxin A, B, or C (k-casein), alpha-lactorphins (alpha-lactalbumin), beta-lactorphin (beta-lactoglobulin) or lactoferroxins (lactoferrin) [2].
• A PCR-restriction fragment length polymorphism (RFLP) genotyping procedure for all currently known CSN3 alleles (CSN3A, CSN3B, CSN3C, CSN3E, CSN3F, CSN3G) was developed [3].
• The quarter-embryos were sexed by polymerase chain reaction (PCR) using BRY.1, Bov97M and ZFX/ZFY loci, and then genotyped for k-casein, bovine leukocyte adhesion deficiency (BLAD) and microsatellite D9S1 [4].
• The PCR products were digested in order to genotype the k-casein gene [5].

Biological context of CSN3

• SSCP analysis at the bovine CSN3 locus discriminates six alleles corresponding to known protein variants (A, B, C, E, F, G) and three new DNA polymorphisms (H, I, A1) [6].
• Genotyping of 30 cattle breeds from four continents revealed a geographically associated distribution of haplotypes, mainly defined by frequencies of alleles at CSN1S1 and CSN3 [7].
• In milk samples from 549 cows of the breeds Danish Jersey, Red Danish Dairy Cattle (RDM), and Black and White Danish Dairy Cattle (SDM) the genetic polymorphisms of the alpha-s1, beta and k-casein and beta=lactoglobulin (beta-Lg) loci were determined by isoelectric focusing in agarose gels [8].
• For Jersey cows, significant differences in the gene frequencies from the results of the 1966 investigation were found for alpha-s1 and k-casein and beta-Lg [8].
• Subsequently, two sets of PCRs were performed using Y chromosome, k-casein and beta-lactoglobulin gene specific primers, followed by electrophoretic analysis of the PCR products [5].

Associations of CSN3 with chemical compounds

• Kinetic parameters have been determined for the reaction between milk-clotting chymosin (EC 3.4.23.4) and a series of peptides (or their methyl esters) including the amino acid sequence around the enzyme-sensitive Phe(105)-Met (106) bond the bovine k-casein [9].

Other interactions of CSN3

• The molecular events occurring during the primary phase of chymosin action on k-casein are discussed [10].

Analytical, diagnostic and therapeutic context of CSN3

• In order to characterize the two new kappa-casein variants F and G (CSN3F and CSN3G) recently detected in Ayrshire and Pinzgauer cattle, exon IV of CSN3 from heterozygous animals was amplified by polymerase chain reaction (PCR), cloned and sequenced [3].
• Polymorphism in the bovine kappa-casein (CSN3) gene and the 5'-flanking region: sequence analysis of CSN3 A and B alleles [11].

References