Holocarboxylase synthetase chromatin

Biotin is also covalently attached to histones, but the abundance of biotinylated histones is low. It is unclear whether the eifects of histone biotinylation in gene repression and genome stability are mediated by histone biotinylation or by interactions of holocarboxylase synthetase with other chromatin proteins. 

Bao, B., Pestinger, V., Hassan, Y.I., Borgstahl, G.E.O., Kolar, C., and Zempleni, J., 2011. Holocarboxylase synthetase is a chromatin protein and interacts directly with histone H3 to mediate biotinylation of K9 and K18. Journal of Nutritional Biochemistry. 22 470-475. 

Gralla, M., Camporeale, G., and Zempleni, J., 2008. Holocarboxylase synthetase regulates expression of biotin transporters by chromatin remodeling events at the SMVT locus. The Journal of Nutritional Biochemistry. 19 400 08. 

SINGH, D., PANNIER, A. K., ZEMPLENI, J. (2011) Identification of holocarboxylase synthetase chromatin binding sites using the DamID technology. Anal. Biochem., 413,55-59. 

Biotin is central to the metabolism of carbohydrates, amino acids, and lipids as biotin is the prosthetic group of the carboxylases. In addition to this metabolic function, biotin influences transcription in organisms ranging from bacteria to humans. Biotin exerts complex effects on cell cycle and gene transcription through epigenetic mechanisms. Nuclear biotin holocarboxylase synthetase seems to interact with other chromatin proteins to form a multiprotein gene repressor complex. 

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