Barrier-to-autointegration factor--a BAFfling little protein.

Barrier-to-autointegration factor (BAF) is an abundant, highly conserved, small and essential protein that binds to dsDNA, chromatin, nuclear lamina proteins, histones and various transcription factors. It was discovered as a cellular component of retrovirus pre-integration complex that inhibits their autointegration in vitro. BAF is also required for many cellular functions, including the higher-order organization of chromatin and the transcription of specific genes. Recent findings suggest further roles for BAF, including nuclear envelope assembly, regulating specific developmental processes and regulating retrovirus infectivity. At least some of these roles are controlled by phosphorylation of the BAF N-terminus by the vaccinia-related kinase. Here, we give an overview of recent advances in the field of BAF with special emphasis on evolution, interacting partners and functions.

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[37]  A. Gronenborn,et al.  Solution structure of the cellular factor BAF responsible for protecting retroviral DNA from autointegration , 1998, Nature Structural Biology.

[38]  R. Siliciano,et al.  Barrier-to-Autointegration Factor BAF Binds p55 Gagand Matrix and Is a Host Component of Human ImmunodeficiencyVirus Type 1Virions , 2003, Journal of Virology.

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[40]  N. Daigle,et al.  LAP2α and BAF transiently localize to telomeres and specific regions on chromatin during nuclear assembly , 2004, Journal of Cell Science.

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[47]  Youichi Suzuki,et al.  Regulatory Mechanisms by Which Barrier-to-Autointegration Factor Blocks Autointegration and Stimulates Intermolecular Integration of Moloney Murine Leukemia Virus Preintegration Complexes , 2002, Journal of Virology.

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[50]  P. Askjaer,et al.  Caenorhabditis elegans BAF‐1 and its kinase VRK‐1 participate directly in post‐mitotic nuclear envelope assembly , 2007, The EMBO journal.

[51]  A. Engelman,et al.  Wild-Type Levels of Human Immunodeficiency Virus Type 1 Infectivity in the Absence of Cellular Emerin Protein , 2006, Journal of Virology.

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[53]  K. Takeyasu,et al.  Dissociation of Emerin from Barrier-to-autointegration Factor Is Regulated through Mitotic Phosphorylation of Emerin in a Xenopus Egg Cell-free System* , 2005, Journal of Biological Chemistry.

[54]  J. Rodríguez-Sánchez,et al.  Identification of the Autoantigen HB as the Barrier-to-Autointegration Factor* , 2003, Journal of Biological Chemistry.

[55]  Miriam Segura-Totten,et al.  Barrier-to-autointegration factor-like (BAF-L): a proposed regulator of BAF. , 2006, Experimental cell research.

[56]  R. Nichols,et al.  The vaccinia-related kinases phosphorylate the N' terminus of BAF, regulating its interaction with DNA and its retention in the nucleus. , 2006, Molecular biology of the cell.

[57]  M Krause,et al.  Barrier-to-autointegration factor (BAF) bridges DNA in a discrete, higher-order nucleoprotein complex. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[58]  Juliet A. Ellis,et al.  The inner nuclear membrane protein Emerin regulates β‐catenin activity by restricting its accumulation in the nucleus , 2006, The EMBO journal.

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[60]  Y. Hiraoka,et al.  BAF is required for emerin assembly into the reforming nuclear envelope. , 2001, Journal of cell science.

[61]  R. Foisner,et al.  LEM2 is a novel MAN1-related inner nuclear membrane protein associated with A-type lamins , 2005, Journal of Cell Science.

[62]  J. Pérez-Ortín,et al.  SRC1: an intron‐containing yeast gene involved in sister chromatid segregation , 2002, Yeast.

[63]  K. Wilson,et al.  LAP2 binds to BAF·DNA complexes: requirement for the LEM domain and modulation by variable regions , 2001, The EMBO journal.

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