An alternatively spliced isoform of the Spi-B transcription factor

Biochem Biophys Res Commun. 1996 Jun 14;223(2):257-63. doi: 10.1006/bbrc.1996.0881.

Abstract

Spi-B is an Ets transcription factor related to the oncoprotein Spi-1/PU.1 and highly expressed in B lymphoid cells. The Ets proteins share a conserved Ets domain that mediates specific DNA binding. Spi-B binds DNA sequences containing a core 5'-GGAA-3' and activates transcription through this motif. Up to date, the biological function of Spi-B remains unknown. Here, we describe the characterization of an alternatively spliced variant of Spi-B, named deltaSpi-B, which has lost the Ets domain. In B lymphoid cells, deltaspi-B and spi-B mRNAs were present simultaneously in a ratio of around 10%. DeltaSpi-B product was not able to bind DNA and was recovered in cytoplasmic cellular extracts. We raise the hypothesis that delta Spi-B might affect Spi-B function by recruiting factors involved in Spi-B activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alternative Splicing*
  • Amino Acid Sequence
  • B-Lymphocytes / metabolism*
  • Base Sequence
  • Burkitt Lymphoma / metabolism*
  • Cell Line
  • DNA Primers
  • DNA, Complementary
  • DNA-Binding Proteins / biosynthesis*
  • DNA-Binding Proteins / genetics
  • Exons
  • Gene Expression
  • Genomic Library
  • Humans
  • Introns
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • RNA, Messenger / metabolism*
  • Recombinant Proteins / biosynthesis
  • Transcription Factors / biosynthesis*
  • Transcription Factors / genetics
  • Transfection
  • Tumor Cells, Cultured

Substances

  • DNA Primers
  • DNA, Complementary
  • DNA-Binding Proteins
  • RNA, Messenger
  • Recombinant Proteins
  • Transcription Factors
  • SPIB protein, human

Associated data

  • GENBANK/X66079
  • GENBANK/X96998