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.
Takahashi
Ichiro
I
Division of Genetic Resources, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640, Japan. itakahas@nih.go.jp
Kameoka
Yosuke
Y
Hashimoto
Katsuyuki
K
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