Avtor/Urednik		Sušnik, Simona
Naslov		Kvantifikacija alelno specifičnih mRNA za kapa-kazein v mlečni žlezi krav
Prevedeni naslov		Quantification of allele specific kappa-casein mRNA in the bovine mammary gland
Tip		monografija
Kraj izdaje		Domžale
Založnik		Medicinska fakulteta
Leto izdaje		1998
Obseg		str. 86
Jezik		slo
Abstrakt		The major milk proteins in cattle are encoded by six polymorphic loci. Some of them demonstrate differential allelic expression in heterozygous animals. Different techniques have been used for the estimation of relative proportions of mRNA A and B for kappa-casein in heterozygous cows. Techniques based on densitometric evaluation of nonradioactively labeled RT-PCR products were less suitable due to the narrow window of linear relation between the signal intensity and concentration of the PCR product. Quantification of the allele specific mRNA molecules using restriction polymorphisms did not provide expected results either. This fact was predominantly due to the heteroduplex formation between both allelic variants. This was the reason, that the amount of the uncleaved variant was overestimated in this assay. The allele specific amplification and use of an internal control were in our hands the most reliable method for the quantification of allele specific mRNA transcripts. The analysis of fluorescentlly labeled allele specific fragments using capillary electrophoresis system allowed us determination of the relative proportion between allelic variants for ic-casein in the lactating mammary gland of the heterozygous cows (kappa-CN AB). Higher proportion of the B variant was always found (A:B = 43.5:56.5), which is in agreement with the relative allelic ratio estimated at the protein level. The model of heterozygous animals enabled us to study allelic expression at the k-casein locus in the same genetic and environmental background. Our results confirm the previous finding of differential allelic production of kappa-casein in dairy cattle, suggesting either transcriptional or posttranscriptional control of gene expression at kappa-casein locus.
Deskriptorji		CASEINS ALLELES RNA, MESSENGER CATTLE POLYMERASE CHAIN REACTION ELECTROPHORESIS, CAPILLARY BLOTTING, NORTHERN CHROMATOGRAPHY, HIGH PRESSURE LIQUID POLYMORPHISM, RESTRICTION FRAGMENT LENGTH GENOTYPE