Testis chromatin

Faraone-Mennella MR, De Lucia F, Gentile N et al. In vitro poly(ADP-ribosyl)ated histones Hla and Hit modulate rat testis chromatin differentially. J Cell Biochem 1999 76 20-29. 

The Starting material used for preparing both nucleoprotamines and protamines is sperm heads or testis chromatin of fish obtained from freshly collected mature milts or sperm freshly drawn from mature testes. These mature milts or sperm contain essentially only one type of cell, spermatozoa, although the former often contain immature sperm cells and connective tissues which must be removed. Ways of preparing sperm heads, chromatin, nucleoprotamines, and protamines will be briefly reviewed in this chapter ... 

For their study of the developmental changes in chromosomal composition and template activity during maturation of trout testis, Marushige and Dixon (1969) applied the method of Marushige and Bonner (1966) for liver chromatin and obtained testis chromatin with a consistent recovery of over 80% relative to DNA content. 

Messenger RNAs for H2A.Bbd have been detected in human testis, fibroblasts and lymphocytes [77], but little is known about the amount of H2A.Bbd protein in these or other human cell types or about its presence in other species. The distribution of H2A.Bbd in chromatin was examined by expressing epitope-tagged or GFP-tagged H2A.Bbd in cultured cells. These studies revealed a striking deficiency of H2A.Bbd in the inactive X chromosome, leading to its name which stands for Histone H2A Barr-body deficient [77]. The distribution of H2A.Bbd overlapped extensively with that of H4 acetylated on lysine 12, suggesting that H2A.Bbd may preferentially associate with transcriptionally active chromatin. 

We have recently shown that, in vitro, poly(ADP-ribosyl)ation of nucleosomes either by purified poIy(ADP-ribose) polymerase [8] or by the endogenous chromatin bound enzyme [9] leads to relaxation of the chromatin superstructure throu histone HI modification. To test the reversibility of this phenomenon, we have used partially purified bull testis poly(ADP-ribose) glycohydrolase [10], which splits the ribosyl-ribose bond between two ADP-ribose units and produces ADP-ribose [11,12]. Changes of the nucleosome structure were examined by electron microscopy and by ultra-centrifugation, and the poly(ADP-ribosyl)ated histones were characterized. 

Levy-Wilson B (1981) ADP-ribosylation of trout testis chromosomal proteins Distribution of ADP-ribosylated proteins among DNase 1-sensitive and -resistant chromatin domains. Arch Biochem Biophys 208 528-534... 

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