TY - JOUR
T1 - Absolute quantification of BACH1 and BACH2 transcription factors in B and plasma cells reveals their dynamic changes and unique roles
AU - Kurasawa, Takeshi
AU - Muto, Akihiko
AU - Matsumoto, Mitsuyo
AU - Ochiai, Kyoko
AU - Murayama, Kazutaka
AU - Igarashi, Kazuhiko
N1 - Publisher Copyright:
© 2024 The Author(s). Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
PY - 2024/12/1
Y1 - 2024/12/1
N2 - Changes in the absolute protein amounts of transcription factors are important for regulating gene expression during cell differentiation and in responses to changes in the cellular and extracellular environment. However, few studies have focused on the absolute quantification of mammalian transcription factors. In this study, we established an absolute quantification method for the transcription factors BACH1 and BACH2, which are expressed in B cells and regulated by direct heme binding. The method used purified recombinant proteins as controls in western blotting and was applied to mouse naïve B cells in the spleen, as well as activated B cells and plasma cells. BACH1 was present in naïve B cells at approximately half the levels of BACH2. In activated B cells, BACH1 decreased compared to naïve B cells, whilst BACH2 increased. In plasma cells, BACH1 increased back to the same extent as in naïve B cells, whilst BACH2 was not detected. Their target genes, Prdm1 and Hmox1, were highly induced in plasma cells. BACH1 was found to undergo degradation with lower concentrations of heme than BACH2. Therefore, BACH1 and BACH2 are similarly abundant in B cells but differ in heme sensitivity, potentially regulating gene expression differently depending on their heme responsiveness.
AB - Changes in the absolute protein amounts of transcription factors are important for regulating gene expression during cell differentiation and in responses to changes in the cellular and extracellular environment. However, few studies have focused on the absolute quantification of mammalian transcription factors. In this study, we established an absolute quantification method for the transcription factors BACH1 and BACH2, which are expressed in B cells and regulated by direct heme binding. The method used purified recombinant proteins as controls in western blotting and was applied to mouse naïve B cells in the spleen, as well as activated B cells and plasma cells. BACH1 was present in naïve B cells at approximately half the levels of BACH2. In activated B cells, BACH1 decreased compared to naïve B cells, whilst BACH2 increased. In plasma cells, BACH1 increased back to the same extent as in naïve B cells, whilst BACH2 was not detected. Their target genes, Prdm1 and Hmox1, were highly induced in plasma cells. BACH1 was found to undergo degradation with lower concentrations of heme than BACH2. Therefore, BACH1 and BACH2 are similarly abundant in B cells but differ in heme sensitivity, potentially regulating gene expression differently depending on their heme responsiveness.
KW - absolute quantification
KW - B cell
KW - BACH1
KW - BACH2
KW - BTB and CNC homology 1
KW - BTB and CNC homology 2
KW - heme metabolism
KW - iron metabolism
KW - plasma cell
KW - transcription factor
UR - http://www.scopus.com/inward/record.url?scp=85211747207&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85211747207&partnerID=8YFLogxK
U2 - 10.1093/jb/mvae065
DO - 10.1093/jb/mvae065
M3 - Article
C2 - 39323025
AN - SCOPUS:85211747207
SN - 0021-924X
VL - 176
SP - 449
EP - 459
JO - Journal of Biochemistry
JF - Journal of Biochemistry
IS - 6
ER -