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Control of B cell production by the adaptor protein lnk. Definition Of a conserved family of signal-modulating proteins.

ABSTRACT: Lnk is an SH2 domain-containing adaptor protein expressed preferentially in lymphocytes. To illuminate the importance of Lnk, we generated lnk(-/-) mice. Whereas T cell development was unaffected, pre-B and immature B cells accumulated in the spleens. In the bone marrow, B-lineage cells were proportionately increased, reflecting enhanced production of pro-B cells that resulted in part from hypersensitivity of precursors to SCF, the ligand for c-kit. Hence, Lnk ordinarily acts to regulate B cell production. Further characterization of lnk(-/-) mice also revealed that full-length Lnk is a 68 kDa protein containing a conserved proline-rich region and a PH domain. Lnk is a representative of a multigene adaptor protein family whose members act, by analogy with Lnk, to modulate intracellular signaling.

SUBMITTER: Takaki S

PROVIDER: S-EPMC5291696 | biostudies-literature | 2000 Nov

REPOSITORIES: biostudies-literature

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Control of B cell production by the adaptor protein lnk. Definition Of a conserved family of signal-modulating proteins.

Takaki S S Sauer K K Iritani B M BM Chien S S Ebihara Y Y Tsuji K K Takatsu K K Perlmutter R M RM

Immunity 20001101 5

Lnk is an SH2 domain-containing adaptor protein expressed preferentially in lymphocytes. To illuminate the importance of Lnk, we generated lnk(-/-) mice. Whereas T cell development was unaffected, pre-B and immature B cells accumulated in the spleens. In the bone marrow, B-lineage cells were proportionately increased, reflecting enhanced production of pro-B cells that resulted in part from hypersensitivity of precursors to SCF, the ligand for c-kit. Hence, Lnk ordinarily acts to regulate B cell ...[more]

PMID: 11114373

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The Lnk/SH2B adaptor provides a fail-safe mechanism to establish the Insulin receptor-Chico interaction.

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| S-EPMC3637499 | biostudies-literature

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