SAM (sterile alpha motif) domain of Neurabin-like (Neural actin-binding) subfamily is a putative protein-protein interaction domain. This group currently includes the SAM domains of neurobin-I, SAMD14 and neurobin-I/SAMD14-like proteins. Most are multidomain proteins and in addition to SAM domain they contain other protein-binding domains such as PDZ and actin-binding domains. Members of this subfamily participate in signal transduction. Neurabin-I is involved in the regulation of Ca signaling intensity in alpha-adrenergic receptors; it forms a functional pair of opposing regulators with neurabin-II. Neurabins are expressed almost exclusively in neuronal cells. They are known to interact with protein phosphatase 1 and inhibit its activity; they also can bind actin filaments; however, the exact role of the SAM domain is unclear, since SAM doesn't participate in these interactions.