Fig. 2.

Characterization of reconstituted c-myb^−/− mutants. (A) Genotypes of offspring embryos resulting from in-crosses of c-myb^+/− heterozygous fish and reconstituted female and male c-myb^−/− mutant fish, respectively. The fecundity of reconstituted transplant recipients is indistinguishable from wild-type fish. The number of wild-type (Top panels), heterozygous (Middle panels), and homozygous mutant (Bottom panels) embryos are indicated as are representative sequence traces. (B) Macroscopic phenotype of the head kidney in the offspring of reconstituted c-myb^−/− mutants. (Scale bar, 1 mm.) (C) Expression of adult hemoglobin alpha (aα) and beta (aβ) genes in WKM cells of wild-type (wt), c-myb^−/− mutants; reconstituted mutants (wt>c-myb^−/−); and offspring of reconstituted mutants (wt>c-myb^−/− IC) as determined by RT-PCR at 11–12 wk of age; amplification with ef1α-specific primers serves as a control for cDNA integrity and amount. (D) Flow cytometry analysis of WKM cells from offspring of reconstituted mutant fish (see Fig. 1E legend for explanation of indicated cell populations); profile representative of three fish. (E) Expression of T- and B-cell–specific marker genes in TLEK fish (wild-type strain), c-myb^−/− mutants, rag1- and jak3-deficient donor fish, and c-myb^−/− recipients transplanted with wild-type (transgenic for the ikaros:eGFP reporter), rag1-, and jak3-deficient WKM cells. cd79b, gene encoding the igβ adaptor protein, constituting part of the B-cell receptor in B cells; igm, Ig µ heavy chain gene expressed in B cells; lck, gene encoding a receptor-associated tyrosine kinase expressed in T cells; tcrb, T-cell receptor β chain gene expressed in T cells; tcrd, T-cell receptor δ chain gene expressed in T cells.