Identification of a novel neuroligin in humans which binds to PSD-95 and has a widespread expression.

Neuroligins, first discovered in rat brain, form a family of three synaptically enriched membrane proteins. Using reverse transcription-PCR of human brain polyadenylated RNA and extensive database searches, we identified the human homologues of the three rat neuroligins and a cDNA encoding a fourth member, which we named neuroligin 4. Neuroligin ...
4 has 63-73% amino acid identity with the other members of the human neuroligin family, and the same predicted domain structure. DNA database analyses, furthermore, indicated that a possible fifth neuroligin gene may be present in the human genome. Northern-blot analysis revealed expression of neuroligin 4 in heart, liver, skeletal muscle and pancreas, but barely at all in brain. Overexpression of neuroligin 4 cDNA in COS-7 cells led to the production of a 110 kDa protein. Immunofluorescence analysis demonstrated that the protein was integrated into the plasma membrane. Overexpression of cDNAs encoding neuroligin 4 and the PDZ-domain protein, PSD-95, in COS-7 cells resulted in the formation of detergent-resistant complexes. Neuroligin 4 did not bind to ZO-1, another PDZ-domain protein. Together, our data show that the human neuroligin family is composed of at least one additional member, and suggest that neuroligin 4 may also be produced outside the central nervous system.
Mesh Terms:
Amino Acid Sequence, Animals, Base Sequence, Brain, COS Cells, Carrier Proteins, Chromosome Mapping, DNA Primers, Gene Expression, Humans, Intracellular Signaling Peptides and Proteins, Membrane Proteins, Molecular Sequence Data, Nerve Tissue Proteins, Protein Binding, RNA, Messenger, Rats, Sequence Homology, Amino Acid
Biochem. J.
Date: Jun. 01, 2001
Download Curated Data For This Publication
8756
Switch View:
  • Interactions 1