This entry includes Cytoplasmic FMR1-interacting proteins 1/2 (CYFIP1/2) from humans and their homologues, such as Sra-1 (specifically Rac1-associated protein 1) from Drosophila and PIROGI from Arabidopsis. CYFIP1/2 interact with FMRP (Fragile X messenger ribonucleoprotein 1) which is responsible for pathological manifestations in the Fragile X Syndrome. CYFIP1 interacts with the small GTPase Rac1 [1,2]. CYFIP1 represses cap-dependent translation of mRNA by interacting with the initiation factor eIF4E [3]. CYFIP1 and CYFIP2 are part of the Wiskott-Aldrich syndrome protein-family verprolin-homologous protein (WAVE) complex that regulates actin polymerization at synapses [4]. Drosophila Sra-1 interacts with the Kette and Wasp. It is required for neuronal and bristle development in Drosophila [5]. PIROGI is part of a WAVE complex that activates the ARP2/3 complex and is Involved in regulation of actin organisation [6].

1: A highly conserved protein family interacting with the fragile X mental retardation protein (FMRP) and displaying selective interactions with FMRP-related proteins FXR1P and FXR2P. Schenck A, Bardoni B, Moro A, Bagni C, Mandel JL; Proc Natl Acad Sci U S A 2001;98:8844-8849. PMID:11438699

2: Reduced CYFIP1 in Human Neural Progenitors Results in Dysregulation of Schizophrenia and Epilepsy Gene Networks. Nebel RA, Zhao D, Pedrosa E, Kirschen J, Lachman HM, Zheng D, Abrahams BS; PLoS One. 2016;11:e0148039. PMID:26824476

3: The fragile X syndrome protein represses activity-dependent translation through CYFIP1, a new 4E-BP. Napoli I, Mercaldo V, Boyl PP, Eleuteri B, Zalfa F, De Rubeis S, Di Marino D, Mohr E, Massimi M, Falconi M, Witke W, Costa-Mattioli M, Sonenberg N, Achsel T, Bagni C; Cell. 2008;134:1042-1054. PMID:18805096

4: Alzheimer-related decrease in CYFIP2 links amyloid production to tau hyperphosphorylation and memory loss. Tiwari SS, Mizuno K, Ghosh A, Aziz W, Troakes C, Daoud J, Golash V, Noble W, Hortobagyi T, Giese KP; Brain. 2016;139:2751-2765. PMID:27524794

5: Sra-1 interacts with Kette and Wasp and is required for neuronal and bristle development in Drosophila. Bogdan S, Grewe O, Strunk M, Mertens A, Klambt C; Development. 2004;131:3981-3989. PMID:15269173

6: Interchangeable functions of Arabidopsis PIROGI and the human WAVE complex subunit SRA1 during leaf epidermal development. Basu D, El-Assal Sel-D, Le J, Mallery EL, Szymanski DB; Development. 2004;131:4345-4355. PMID:15294869