MacroH2A1.2 binds the nuclear protein Spop.
X-chromosome inactivation is a phenomenon by which one of the two X chromosomes in somatic cells of female mammals is inactivated for life. The inactivated X chromosomes are covered with Xist (X-inactive specific transcript) RNA, and also enriched with the histone H2A variant, macroH2A1.2. The N-terminal one-third of macroH2A1.2 is homologous to core histone H2A, but the function of the C-terminal two-thirds, which contains a basic, putative leucine zipper domain, remains unknown. In this study, we tried analyzing protein-protein interaction with a yeast two-hybrid system to interact with the nonhistone region of mouse macroH2A1.2. The results showed that macroH2A1.2 interacts with mouse nuclear speckled type protein Spop. The Spop protein has a unique composition: an N-terminal MATH, and a C-terminal BTB/POZ domain. Further binding domain mapping in a glutathione-S-transferase (GST) pull-down experiment revealed that macroH2A1.2 binds the MATH domain of Spop, which in turn binds to the putative leucine zipper domain of macroH2A1.2.
Division of Genetic Resources, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640, Japan. itakahas@nih.go.jp
Ichiro
I
Takahashi
Yosuke
Y
Kameoka
Katsuyuki
K
Hashimoto
D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000302:isolation & purification; D004303:Dosage Compensation, Genetic; D006657:Histones / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins; D020798:Two-Hybrid System Techniques; D043743:Ubiquitin-Protein Ligase Complexes
D018076:DNA, Complementary; D006657:Histones; D009687:Nuclear Proteins; D012097:Repressor Proteins; C120756:macroH2A histone; C509762:Spop protein, mouse; D043743:Ubiquitin-Protein Ligase Complexes