AbI-interactor (Abi) proteins are targets of AbI-family nonreceptor tyrosine kinases and are required for Rac-dependent cytoskeletal reorganization in response to growth factor stimulation. We asked if the expression, phosphorylation, and cellular localization of Abi-1 and Abi-2 supports a role for these proteins in AbI signaling in the developing and adult mouse nervous system. In mid to late-gestation embryos, abi-2 message is elevated in the central and peripheral nervous systems (CNS and PNS). Abi-l mRNA is present, but not enhanced, in the CNS, and is not observed in PNS structures. Abi proteins from brain iysates undergo changes in apparent molecular weight and phosphorylation with increasing age. In the postnatal brain, abi-1 and abi-2 are expressed most prominently in cortical layers populated by projection neurons. In cultured neurons, Abi-1 and Abi-2 are concentrated in puncta throughout the cell body and processes. Both Abi and AbI proteins are present in synaptosomes and growth cone particles. Therefore, the Abi adaptors exhibit proper expression patterns and subcellular localization to participate in AbI kinase signaling in the nervous system.
ASJC Scopus subject areas
- Molecular Biology
- Cellular and Molecular Neuroscience
- Cell Biology