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Zebrafish B Cell Development without a Pre-B Cell Stage, Revealed by CD79 Fluorescence Reporter Transgenes.

ABSTRACT: CD79a and CD79b proteins associate with Ig receptors as integral signaling components of the B cell Ag receptor complex. To study B cell development in zebrafish, we isolated orthologs of these genes and performed in situ hybridization, finding that their expression colocalized with IgH-? in the kidney, which is the site of B cell development. CD79 transgenic lines were made by linking the promoter and upstream regulatory segments of CD79a and CD79b to enhanced GFP to identify B cells, as demonstrated by PCR analysis of IgH-? expression in sorted cells. We crossed these CD79-GFP lines to a recombination activating gene (Rag)2:mCherry transgenic line to identify B cell development stages in kidney marrow. Initiation of CD79:GFP expression in Rag2:mCherry+ cells and the timing of Ig H and L chain expression revealed simultaneous expression of both IgH-?- and IgL-?-chains, without progressing through the stage of IgH-?-chain alone. Rag2:mCherry+ cells without CD79:GFP showed the highest Rag1 and Rag2 mRNAs compared with CD79a and CD79b:GFP+ B cells, which showed strongly reduced Rag mRNAs. Thus, B cell development in zebrafish does not go through a Raghi CD79+IgH-?+ pre-B cell stage, different from mammals. After the generation of CD79:GFP+ B cells, decreased CD79 expression occurred upon differentiation to Ig secretion, as detected by alteration from membrane to secreted IgH-? exon usage, similar to in mammals. This confirmed a conserved role for CD79 in B cell development and differentiation, without the requirement of a pre-B cell stage in zebrafish.

SUBMITTER: Liu X

PROVIDER: S-EPMC5563169 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Zebrafish B Cell Development without a Pre-B Cell Stage, Revealed by CD79 Fluorescence Reporter Transgenes.

Liu Xingjun X Li Yue-Sheng YS Shinton Susan A SA Rhodes Jennifer J Tang Lingjuan L Feng Hui H Jette Cicely A CA Look A Thomas AT Hayakawa Kyoko K Hardy Richard R RR

Journal of immunology (Baltimore, Md. : 1950) 20170724 5

CD79a and CD79b proteins associate with Ig receptors as integral signaling components of the B cell Ag receptor complex. To study B cell development in zebrafish, we isolated orthologs of these genes and performed in situ hybridization, finding that their expression colocalized with IgH-μ in the kidney, which is the site of B cell development. CD79 transgenic lines were made by linking the promoter and upstream regulatory segments of CD79a and CD79b to enhanced GFP to identify B cells, as demons ...[more]

PMID: 28739882

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Dataset Information

Zebrafish B Cell Development without a Pre-B Cell Stage, Revealed by CD79 Fluorescence Reporter Transgenes.

Publications

Zebrafish B Cell Development without a Pre-B Cell Stage, Revealed by CD79 Fluorescence Reporter Transgenes.

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