Figure 2.

A proposed model for Sigma1 as an oligomerization adaptor in signaling pathways controlling key cellular functions. Gleaning from biophysical data [77,78] and bacterial models [82], it is proposed here that SigmaR1 serves as an oligomerization adaptor that forms higher-order complexes in key pathways and involves GTPases such as Rac1 and scaffold molecules such as IQGAP1 to ensure specificity of complex formation and thus cellular functions of common molecules. The cellular membrane represents plasma or any organelle membrane where SigmaR1 is located. Secretion depicts vesicular-mediated exocytic activities, including neurotransmitters or Golgi transport.