Maturation promoting factor activation

Murray, A. W., Solomon, M. J., and Kirschner, M. W. (1989). The role of cyclin synthesis and degradation in the control of maturation promoting factor activity. Nature 339 280-286. 

Madgwick S, Nixon VL, Chang HY, Herbert M, Levasseur M, Jones KT. 2004. Maintenance of sister chromatid attachment in mouse eggs through maturation-promoting factor activity. Dev Biol 275(1) 68-81. 

Fulka, J., Jr., Jung, T., and Moor, R. M. (1992). The fall of biological maturation promoting factor (MPF) and histone HI kinase activity during anaphase and telophase in mouse oocytes. Mol. Reprod. Devel. 32 378-382. 

Sorenson, R. A., Cyert, M. S., and Pedersen, R. A. (1985). Active maturation-promoting factor is present in mature mouse oocytes. J. Cell Biol. 100 1637-1640. 

Unfortunately, this field is made difficult for a student by the terminology used by biochemists. For example, there is a protein kinase that regulates the cycle between G2 and M, i.e. the second restriction point. This protein is known as maturation (or mitosis) promoting factor, since it promotes entry into mitosis. It phosphorylates a protein, probably a transcription factor, in the nucleus. The kinase has a molecular mass of 34kDa. Hence it is known as p34 cell division kinase, abbreviated to p34-cdc and, since it is regulated at restriction point 2, it is known as p34-cdc-2 protein, which is sometimes written as p34°. This kinase is normally inactive until it binds a cyclin. Hence the active maturation-promoting factor is, in fact, a protein kinase-cyclin complex, which is referred to as p34° °-cyclin complex. It is hoped that this piece of information may help a student (or lecturer from another field) to understand one part of a review article that contains the abbreviation p34° -cyclin complex, without explanation, or other similar pieces of biochemical shorthand. 

Cyclin B/CDKl is the primary regulator of the G2/M transition, and its activity is required for entry into mitosis. It was termed the maturation-promoting factor (MPF) because it was originally shown to be essential for Xenopus oocytes maturation... 

Balamurugan K, Haider S. 1998. Partial purification of maturation-promoting factor from catfish, Claiias batrachus identification as the histone HI kinase and its periodic activation. Comp Biochem Physiol C Pharmacol Toxicol Endocrinol 120(3) 329-342. 

Choi T, Rulong S, Resau J, Fukasawa K, Matten W, Kuriyama R, Mansour S, Ahn N, Vande Woude GF. 1996. Mos/mitogen-activated protein kinase can induce early meiotic phenotypes in the absence of maturation-promoting factor a novel system for analyzing spindle formation during meiosis I. Proc Natl Acad Sci U S A 93(10) 4730-4735. 

I.4. Growth factor activity. Recent studies have demonstrated that lactotransferrin may promote growth of intestinal epithelial cells, suggesting that it might play a part in maturation of the intestine in the newborn (for reviews, see refs. [161,162]), of B-lymphocytes [188] and of PHA-activated peripheral blood lymphocytes [189,190]. 

In amphibian eggs (fig. 10.2), the cell cycle has a simple form as it consists in the periodic alternation of mitosis and interphase. Mitosis is associated with the activation of a factor known as maturation (or mitosis) promoting factor (MPF). Activation of MPF is triggered by the building up to a threshold of cyclin, a protein whose name reflects its... 

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