Early expression of a T-cell receptor beta-chain transgene suppresses rearrangement of the V gamma 4 gene segment.
beta transgenic mice have a T-cell receptor beta-chain gene that is prematurely expressed on the surface of CD4- CD8- thymocytes and paired with an uncharacterized non-T-cell receptor alpha-chain polypeptide. The rearrangement of the T-cell receptor variable region gamma chain gene segment V gamma 4, a component of the gamma-chain gene that is rearranged and expressed preferentially on thymocytes of normal adult mice, is severely repressed in beta transgenic mice. Consequently no gamma delta T-cell receptor heterodimers are detectable on the surface of adult thymocytes or splenic T cells. These results indicate that cells expressing alpha beta or gamma (V gamma 4)-delta TCRs originate from a common precursor in which the first productive rearrangement of either the beta or gamma locus determines the further differentiation pathway into either alpha beta or gamma delta T cells. The repression of V gamma 4 rearrangement by a preexisting beta-chain gene may be indicative of one of several mechanisms which ensure that gamma delta and alpha beta receptors do not as a rule appear on the surface of the same cell.
von Boehmer
H
H
Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge 02139.
Bonneville
M
M
Ishida
I
I
Ryser
S
S
Lincoln
G
G
Smith
R T
RT
Kishi
H
H
Scott
B
B
Kisielow
P
P
Tonegawa
S
S
D000483:Alleles; D000818:Animals; D002874:Chromosome Mapping; D005786:Gene Expression Regulation; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D013601:T-Lymphocytes / Q000032:analysis
D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta