Genomic localization of the human genes TAF1A, TAF1B and TAF1C, encoding TAF(I)48, TAF(I)63 and TAF(I)110 subunits of class I general transcription initiation factor SL1.
Human SL1 is a general transcription initiation factor (GTF) essential for RNA polymerase I to start rRNA synthesis at class I promoters. It is comprised of the TATA box-binding protein (TBP) and three TBP-associated factors (TAF(I)48, TAF(I)63 and TAF(I)110). We have determined that the human genes TAF1A, TAF1B and TAF1C, encoding these three TAF(I) polypeptides, are localized at lq42, 2p25 and 16q24, respectively. All three genes are present as single copies in the human genome and map to different chromosomes, as shown by somatic cell hybrid panel and radiation hybrid panel analysis and FISH. Two of these genes, TAF1C and TAF1B, are transcribed into multiple RNAs, as determined through Northern analysis of mRNA from various human organs and cell lines. If translated into different polypeptides, this could result in production of variant isoforms of SL1 with different activation potentials.
Di Pietro
C
C
Dipartimento di Scienze biomediche, Sezione di Biologia generale, cellulare e di Genetica molecolare, Università di Catania, Catania, Italy.
Rapisarda
A
A
Amico
V
V
Bonaiuto
C
C
Viola
A
A
Scalia
M
M
Motta
S
S
Amato
A
A
Engel
H
H
Messina
A
A
Sichel
G
G
Grzeschik
K
K
Purrello
M
M
D000483:Alleles; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002885:Chromosomes, Human, Pair 16 / Q000235:genetics; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D008040:Genetic Linkage / Q000235:genetics; D006801:Humans; D006822:Hybrid Cells; D017404:In Situ Hybridization, Fluorescence; D020161:Physical Chromosome Mapping; D035463:Pol1 Transcription Initiation Complex Proteins; D012150:Polymorphism, Restriction Fragment Length; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics*; D014407:Tumor Cells, Cultured
D004268:DNA-Binding Proteins; D035463:Pol1 Transcription Initiation Complex Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; C091131:TAF1A protein, human; C091129:TAF1B protein, human; C486319:TAF1C protein, human; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; D014157:Transcription Factors; C063660:transcription initiation factor TIF-IB