Isoforms of Kalirin, a neuronal Dbl family member, generated through use of different 5'- and 3'-ends along with an internal translational initiation site

Richard C. Johnson, Peter Penzes, Betty A. Eipper, Richard E. Mains*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

72 Scopus citations

Abstract

Kalirin is a neuron-specific GDP/GTP exchange factor for Rho subfamily GTP-binding proteins. The major Kalirin transcripts in adult rat brain were identified. Most include a Sec14p-like putative lipid-binding motif followed by nine spectrin-like repeats and a Dbl homology/pleckstrin homology (DH-PH) domain. Kalirin proteins with four different NH2 termini are generated through the use of five different 5'-ends; three of the proteins differ only at the extreme N-H2 terminus, and one is truncated because translation is initiated at a methionine in the 5th spectrin repeat. Four different 3'-ends yield Kalirin proteins with additional functional domains. Kalirin-7 (7- kilobase pair mRNA) terminates with a PDZ-binding motif, which in Kalirin-8 is replaced by an SH3 domain. Kalirin-9 contains another pair of DH-PH and SH3 domains. Kalirin-12 additionally encodes a putative Ser/Thr protein kinase. Antisera specifiC for different COOH termini established Kalirin-7 as the most abundant in cortex, with significant amounts of Kalirin-9 and Kalirin-12; Kalirin-7 was less prevalent in cerebellum and olfactory bulb. Kalirin proteins lacking the Sec14p-like domain and first four spectrin-like repeats were much less prevalent. Form-specific antisera demonstrated that different forms of Kalirin were localized to distinct subcellular regions of cultured neurons. Members of the family of Kalirin proteins may subserve different functions at these different locations.

Original languageEnglish (US)
Pages (from-to)19324-19333
Number of pages10
JournalJournal of Biological Chemistry
Volume275
Issue number25
DOIs
StatePublished - Jun 23 2000

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Isoforms of Kalirin, a neuronal Dbl family member, generated through use of different 5'- and 3'-ends along with an internal translational initiation site'. Together they form a unique fingerprint.

Cite this