TBP2, a vertebrate-specific member of the TBP family, is required in embryonic development of zebrafish.
TATA binding protein (TBP) is a key regulator of RNA polymerase transcription. It binds to core promoters, often in large multiprotein complexes, and nucleates RNA polymerase II (Pol II) transcription initiation. In addition to the previously described TBP-like factor present in metazoans (TLF/TRF2/TRP/TLP), we describe a third, vertebrate-specific member of the TBP protein family from zebrafish, called TBP2. Evolutionary conserved TBP2 homologs were also found in human, mouse, frog, and pufferfish. The N-terminal domains of TBP2s are divergent amongst themselves and different from those of TBPs; however, the core domain of TBP2s and TBPs are almost identical. TBP2 binds the TATA box, interacts with TFIIA and TFIIB (similarly to TBP), and can mediate Pol II transcription initiation. However, TBP2 shows contrasting expression patterns in the gonads and during embryonic development in comparison to TBP, suggesting differential function. Knockdown of zebrafish TBP2 results in specific reduction of the protein level, leading to a phenotype, which indicates the requirement of TBP2 for embryonic patterning. The presence of three different TBP family members in vertebrates suggests the existence of developmental stage- and tissue-specific preinitiation complexes with specific requirements for different TBP family members.
Bártfai
Richárd
R
Reproductive Genomics, Temasek Lifesciences Laboratory, 1 Research Link, The National University of Singapore, Singapore 117604, Singapore.
Balduf
Carolin
C
Hilton
Traci
T
Rathmann
Yvonne
Y
Hadzhiev
Yavor
Y
Tora
László
L
Orbán
László
L
Müller
Ferenc
F
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D018076:DNA, Complementary / Q000235:genetics; D040461:Gene Components; D020869:Gene Expression Profiling; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D021101:Radiation Hybrid Mapping; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D035181:TATA-Box Binding Protein / Q000235:genetics* / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics*
D018076:DNA, Complementary; D035181:TATA-Box Binding Protein; D029961:Zebrafish Proteins; C487363:tbpl2 protein, zebrafish