Teneurins, a transmembrane protein family involved in cell communication during neuronal development

Abstract

Teneurins are a unique family of transmembrane proteins conserved from Caenorhabditis elegans and Drosophila melanogaster to vertebrates, in which four paralogs exist. In vertebrates, teneurin expression is most prominent in the developing brain. Based on their distinct, complementary expression patterns, we suggest a possible function in the establishment of proper connectivity in the brain. Functional studies show that teneurins can stimulate neurite outgrowth, but they might also play a role in axon guidance as well as in target recognition and synaptogenesis, possibly mediated by homophilic interactions. Though teneurins are transmembrane proteins, there is evidence that the intracellular domain has a nuclear function, since it can interact with nuclear proteins and influence transcription. Therefore, we speculate that teneurins might be processed by proteolytic cleavage (possibly regulated intramembrane proteolysis), which is triggered by homophilic interactions or, alternatively, by the binding of a still unknown ligand.

Characterization of the teneurin C-terminal associated peptide (TCAP) in the vase tunicate, Ciona intestinalis: A novel peptide system associated with energy metabolism and reproduction

“…With respect to behavior, TCAP-1 is potent at inhibiting stress-induced behaviors in vertebrates as shown in elevated-plus maze (Al Chawaf et al, 2007b;Tan et al, 2008) open-field (Tan et al, 2008), acoustic startle response (Tan et al, 2008;Wang et al, 2005) and cocaine reinstatement studies (Erb et al, in press;Kupferschmidt et al, 2010). The evidence to date suggests that this mechanism is mediated by changes in synaptic plasticity as shown by changes in axon, neurite and dendritic modifications by TCAP-1 (Al Chawaf et al, 2007a;Chand et al, 2012a,b;Tan et al, , 2011a and is supported by a clear regulation of cytoskeletal elements in vertebrates (Chand et al, 2012a,b;2013a,b) and invertebrates Kenzelmann et al, 2007;Mosca et al, 2012;Zhang et al, 2012). However, other studies suggest that this may be only part of the explanation.…”

Ig Superfamily Ligand and Receptor Pairs Expressed in Synaptic Partners in Drosophila

“…These included genes encoding immunoglobulin (Ig) (Fischbach et al, 2009 and Zipursky et al, 2006), leucine-rich repeat (LRR) (de Wit et al, 2011), and epidermal growth factor (EGF) domain-containing proteins (Kenzelmann et al, 2007 and Serafini et al, 1994), as well as many members of the large tetraspanin protein family (Fradkin et al, 2002 and Kopczynski et al, 1996) (Figures 3B and S3). …”

Rhs proteins from diverse bacteria mediate intercellular competition

“…Teneurins are type II integral membrane proteins that help to establish neuronal cell connections during development (30,31). Remarkably, some teneurins carry C-terminal sequences that resemble neuroendocrine signaling peptides (32). These sequences are adjacent to predicted furin cleavage sites, suggesting that the C-terminal peptides are released and transmit signals to neighboring cells.…”