Related Experiment Video
Updated: Mar 2, 2026
An Efficient Single—Person Technique for Milk Sampling from Laboratory Mice
Published on: March 28, 2025
Genetic and nongenetic factors contributing to differences in αS-casein phosphorylation isoforms and other major milk
Z H Fang1, H Bovenhuis2, A Delacroix-Buchet3
1Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France; Animal Breeding and Genomics Centre, Wageningen University and Research, PO Box 338, 6700 AH Wageningen, the Netherlands.
Abstract:
Relative concentrations of αS-casein (αS-CN) phosphorylation isoforms vary considerably among milk of individual cows. We aimed to explore to what extent genetic and other factors contribute to the variation in relative concentrations of αS-CN phosphorylation isoforms and the phosphorylation degree of αS-CN defined as the proportion of isoforms with higher degrees of phosphorylation. We also investigated the associations of genetic variants of milk proteins and casein haplotypes with relative concentrations of αS-CN phosphorylation isoforms and with the phosphorylation degree of αS-CN in French Montbéliarde cattle from the cheese production area of Franche-Comté. Detailed milk protein composition was determined by liquid chromatography coupled with electrospray ionization mass spectrometry from 531 test-day morning milk samples. Parity, lactation stage, and genetic variation of cows contributed to the phenotypic variation in relative concentrations of individual αS-CN phosphorylation isoforms and in the phosphorylation degree of αS-CN. As lactation progressed, we observed a significant increase for relative concentrations of αS-CN isoforms with higher degrees of phosphorylation (αS1-CN-9P, αS2-CN-13P, and αS2-CN-14P) as well as for the phosphorylation degree of both αS1-CN and αS2-CN. Furthermore, the β-CN I variant was associated with a greater proportion of isoforms with lower degrees of phosphorylation (αS1-CN-8P, αS2-CN-10P, and αS2-CN-11P); the β-CN B variant was associated with a greater proportion of isoforms with higher degrees of phosphorylation (αS1-CN-9P, αS2-CN-12P to αS2-CN-14P). The heritability estimates were low to moderate for relative concentrations of αS2-CN phosphorylation isoforms (0.07 to 0.32), high for relative concentrations of αS1-CN-8P (0.84) and αS1-CN-9P (0.56), and moderate for phosphorylation degrees of αS1-CN (0.37) and αS2-CN (0.23). Future studies investigating relations between the phosphorylation degree of αS-CN and technological properties of milk will be beneficial for the dairy industry.
Related Concept Videos
01:29Factors Affecting Protein-Drug Binding: Patient-Related Factors
Age stands as a key determinant in protein-drug binding. Neonates, characterized by low albumin content, experience heightened concentrations of unbound drugs such as phenytoin and...
01:29Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu
02:27Background and Environment Affect Phenotype
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
02:54Protein Kinases and Phosphatases
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
01:18Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In...
01:02Phosphorylation
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...