Purification of a nuclear trans-acting factor involved in the regulated transcription of a human immunoglobulin heavy chain gene.
The expression of the rearranged human immunoglobulin gamma 1 heavy chain gene (HIG1) was shown to be induced through its enhancer by the positive regulatory trans-acting factor(s) that was contained only in cells of B lineage. The trans-acting factors were purified from mouse myeloma NS1 cells, and HIG1-inducing activity was found mainly in fractions of molecular weight 53-127 kd and in a fraction eluted from a heparin-Sepharose column with 0.5 M KCI. This semipurified fraction contained proteins binding to the conserved octamer sequence, ATGCAAAT, in the promoter region, as well as to sequences in the enhancer region. The 0.5 M KCI eluates from a heparin-Sepharose column were applied to a DNA affinity column of synthetic oligonucleotides of the octamer sequence and the sequence TATTTTAGGAAGCAAA in the HpaII-BgIII region of the HIG1 gene enhancer. The protein eluted from the enhancer sequence-specific DNA affinity column showed a strong inducing activity for the HIG1 gene, and the molecular weight of a predominant protein was 96 kd.
Araki
K
K
Department of Molecular Immunology, Kyushu University, Fukuoka, Japan.
Maeda
H
H
Wang
J
J
Kitamura
D
D
Watanabe
T
T
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D004262:DNA Restriction Enzymes; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D015696:Gene Products, tat; D005803:Genes, Immunoglobulin; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D014157:Transcription Factors / Q000302:isolation & purification* / Q000502:physiology; D014158:Transcription, Genetic
D015696:Gene Products, tat; D007143:Immunoglobulin Heavy Chains; D014157:Transcription Factors; D004262:DNA Restriction Enzymes