Kappa casein gen (CSN3) in horse : genetic variability in exon 1 and 4

Hobor, Sebastijan (author), Kunej, Tanja (author), Lenasi, Tina (author), Dovč, Peter (author)

Kappa casein (K-CN) is milk protein that determines the size and specific function of the casein micelles, and its clevage by chymosine is responsible for milk coagulation. Any variation in gene promoter or coding sequence may change the expression of the gene or amino acid sequence, effecting functional properties of the protein. The mature k-cn is encoded by part of the exon 3 and the entire exon 4. Since exon 3 has 33 bp and exon 4 is 497 bp long, the major part of the protein is encoded by exon 4. In this study we identified two SNPs in exon 1 and two in exon 4 of the horse kappa casein gene(CSN3) and genotyped them in three horse breeds. The nucleotide sequence of the first exon was included in this study due to its possible role in the regulation of the CSN3 expression. Because these polymorphisms were analysed for the first time, we used a reference method (RFLP) or at least two other complementig methods (Bi-PASA/PIRA and ASA-PCR/PIRA), for molecular genetic analysis of above mentioned SNPs. The highest variation in genotype frequencies was present in Slovenian cold blood breed. SNPs in exon 4 cause amino acid (AA) change in the mature product, and may very well render chemical/functional properties of the protein. Analysis of the consequences caused bz changes in AA sequence, bz online avaible program tools, comfirmed our hypothesis.

• Language: English
• Keywords: horses, molecular genetics, kappa casein, CSN3, nucleotides, polymorphism, genetic vatiation, amino acids, sequence
• Work type: Not categorized
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publisher: Biotehniška fakulteta
• Year: 2006
• Number of pages: Str. 83-89
• Numbering: Letn. 88, št. 2
• PID: 20.500.12556/RUL-59773
• UDC: 636.1:575
• ISSN on article: 1581-9175
• COBISS.SI-ID: 1971080
• Publication date in RUL: 10.07.2015

HOBOR, Sebastijan, KUNEJ, Tanja, LENASI, Tina and DOVČ, Peter, 2006, Kappa casein gen (CSN3) in horse : genetic variability in exon 1 and 4. Acta agriculturae Slovenica [online]. 2006. Vol. 88, no. 2, p. 83–89. [Accessed 19 March 2025]. Retrieved from: http://www.dlib.si/details/URN:NBN:SI:doc-JMN2C98Y

Record is a part of a journal

• Title: Acta agriculturae Slovenica
• Shortened title: Acta agric. Slov.
• Publisher: Biotehniška fakulteta
• ISSN: 1581-9175
• COBISS.SI-ID: 213840640

Secondary language

• Language: Slovenian
• Title: Kapa kazeinski gen (CSN3) pri konju

Abstract

Kapa kazein (K-CN) je mlečni protein, ki določa velikost in specifično funkcijo kazeinskih micel, njegova razgradnja s kimozinom pa je odgovorna za koagulacijo mleka. Sprememba v promotorju ali kodirajoèem področju gena lahko vpliva na njegovo izražanje, oziroma spremeni aminokislinsko zaporedje, s tem pa vpliva na funkcionalnost proteina. Zrel K-CN protein je deloma kodiran z eksonom 3 in s celotnim eksonom 4. Zaporedje eksona 1 smo vključili v raziskavo, ker je moyno, da ima regulatorno vlogo. Ker je ekson 3 dolg 33 baznih parov, ekson 4 pa ima 497 baznih parov, je pretežni del proteina kodiran z eksonom 4. V tej študiji smo izvedli genetsko analizo dveh nukleotidnih zamenjav v eksonu 1 in dveh v eksonu 4 v genu za kapa kazein (CSN3) pri konju in jih genotipizirali pri treh pasmah. Ker ti polimorfizmi se nikoli niso bili analizirani, smo za genetsko molekularno analizo omenjenih polimorfizmov, uporabili referenčno metodo (RFLP) ali vsaj dve drugi dopolnjujoči metodi (Bi-PASA/PIRA in ASA-PCR/PIRA). Največja raznolikost genotipov je bila prisotna pri Slovenski hladnokrvni pasmi. Nukleotidni zamenjavi v eksonu 4 povzročita zamenjavo aminokislin v končnem produktu, kar pa lahko spremeni kemične/fukcionalne lastnosti proteina. Analiza posledic sprememb aminokislinske sekvence, s programi na internetu, je potrdila naso hipotezo.

• Keywords: konji, molekularna genetika, kapa kazein, CSN3, nukleotidi, polimorfizem, genetska variabilnost, aminokisline, zaporedje