Ontogeny of the murine Ig joining chain gene and protein.
We used Northern blot analysis in order to investigate the ontogeny of the murine joining (J)-chain gene. No J-chain expression was detected in embryonic tissues, including liver, spleen and intestine, but an expression of mu heavy chain was detected in foetal liver at day 17. J-chain expression was detected in the spleen at day 9 and in the intestine at day 15 after birth. Western blot analysis was carried out in order to compare the protein levels of J and mu heavy chains in serum from day 8 to day 24 after birth, using antihuman J chain and antimouse mu chain antibodies. Although mu chain protein could be detected in serum from day 8, J-chain protein was detectable only at day 24. These results suggest that the expression of J chain is a later event than the mu chain in the mouse, which thus differs in embryogenesis from humans.
Kimura
M
M
Nihon University School of Dentistry, Department of Pathology, Tokyo, Japan.
Takahashi
T
T
Iwata
A
A
Matsumoto
N
N
Ogura
Y
Y
Akagi
T
T
Akima
S
S
Kobayashi
K
K
Moro
I
I
D000818:Animals; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007144:Immunoglobulin J-Chains / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics*; D007133:Immunoglobulin Joining Region / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics*; D007148:Immunoglobulin mu-Chains / Q000096:biosynthesis / Q000097:blood / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity
D007144:Immunoglobulin J-Chains; D007133:Immunoglobulin Joining Region; D007148:Immunoglobulin mu-Chains; D012333:RNA, Messenger