Anti-FMR1 Antibody

Fragile X syndrome is a frequent form of inherited mental retardation caused by functional loss of the fragile X mental retardation protein, FMR1, also known as FMRP (1) . FMR1 binds RNA and is associated with polysomes. The encoded protein may be involved in mRNA trafficking from the nucleus to the cytoplasm (2) . A trinucleotide repeat (CGG) in the 5' UTR is normally found at 6-53 copies, but an expansion to 55-230 repeats is the cause of fragile X syndrome (1) . Expansion of the trinucleotide repeat may also cause one form of premature ovarian failure (POF1) (3) .

FMR1 antibody was raised against a 19 amino acid peptide near the carboxy terminus of human FMR1. The immunogen is located within the last 50 amino acids of FMR1.

Expressed in the brain, cerebellum and testis (PubMed:8401578) . Also expressed in epithelial tissues (PubMed:8401578) . Expressed in mature oligodendrocytes (OLGs) (PubMed:23891804) . Expressed in fibroblast (PubMed:24204304) . Expressed in neurons, Purkinje cells and spermatogonias (at protein level) (PubMed:8401578) . Expressed in brain, testis and placenta (PubMed:8504300) . Expressed in neurons and lymphocytes (PubMed:8504300) .

Multifunctional polyribosome-associated RNA-binding protein that plays a central role in neuronal development and synaptic plasticity through the regulation of alternative mRNA splicing, mRNA stability, mRNA dendritic transport and postsynaptic local protein synthesis of a subset of mRNAs (PubMed:16631377, PubMed:18653529, PubMed:19166269, PubMed:23235829, PubMed:25464849) . Plays a role in the alternative splicing of its own mRNA (PubMed:18653529) . Plays a role in mRNA nuclear export (By similarity) . Together with export factor NXF2, is involved in the regulation of the NXF1 mRNA stability in neurons (By similarity) . Stabilizes the scaffolding postsynaptic density protein DLG4/PSD-95 and the myelin basic protein (MBP) mRNAs in hippocampal neurons and glial cells, respectively; this stabilization is further increased in response to metabotropic glutamate receptor (mGluR) stimulation (By similarity) . Plays a role in selective delivery of a subset of dendritic mRNAs to synaptic sites in response to mGluR activation in a kinesin- dependent manner (By similarity) . Plays a role as a repressor of mRNA translation during the transport of dendritic mRNAs to postnyaptic dendritic spines (PubMed:11532944, PubMed:11157796, PubMed:12594214, PubMed:23235829) . Component of the CYFIP1-EIF4E- FMR1 complex which blocks cap-dependent mRNA translation initiation (By similarity) . Represses mRNA translation by stalling ribosomal translocation during elongation (By similarity) . Reports are contradictory with regards to its ability to mediate translation inhibition of MBP mRNA in oligodendrocytes (PubMed:23891804) . Also involved in the recruitment of the RNA helicase MOV10 to a subset of mRNAs and hence regulates microRNA (miRNA) -mediated translational repression by AGO2 (PubMed:14703574, PubMed:17057366, PubMed:25464849) . Facilitates the assembly of miRNAs on specific target mRNAs (PubMed:17057366) . Plays also a role as an activator of mRNA translation of a subset of dendritic mRNAs at synapses (PubMed:19097999, PubMed:19166269) . In response to mGluR stimulation, FMR1-target mRNAs are rapidly derepressed, allowing for local translation at synapses (By similarity) . Binds to a large subset of dendritic mRNAs that encode a myriad of proteins involved in pre- and postsynaptic functions (PubMed:7692601, PubMed:11719189, PubMed:11157796, PubMed:12594214, PubMed:17417632, PubMed:23235829, PubMed:24448548) . Binds to 5'-ACU[GU]-3' and/or 5'-[AU]GGA-3' RNA consensus sequences within mRNA targets, mainly at coding sequence (CDS) and 3'-untranslated region (UTR) and less frequently at 5'- UTR (PubMed:23235829) . Binds to intramolecular G-quadruplex structures in the 5'- or 3'-UTRs of mRNA targets (PubMed:11719189, PubMed:18579868, PubMed:25464849, PubMed:25692235) . Binds to G- quadruplex structures in the 3'-UTR of its own mRNA (PubMed:7692601, PubMed:11532944, PubMed:12594214, PubMed:15282548, PubMed:18653529) . Binds also to RNA ligands harboring a kissing complex (kc) structure; this binding may mediate the association of FMR1 with polyribosomes (PubMed:15805463) . Binds mRNAs containing U-rich target sequences (PubMed:12927206) . Binds to a triple stem-loop RNA structure, called Sod1 stem loop interacting with FMRP (SoSLIP), in the 5'- UTR region of superoxide dismutase SOD1 mRNA (PubMed:19166269) . Binds to the dendritic, small non-coding brain cytoplasmic RNA 1 (BC1) ; which may increase the association of the CYFIP1-EIF4E-FMR1 complex to FMR1 target mRNAs at synapses (By similarity) . Associates with export factor NXF1 mRNA-containing ribonucleoprotein particles (mRNPs) in a NXF2-dependent manner (By similarity) . Binds to a subset of miRNAs in the brain (PubMed:14703574, PubMed:17057366) . May associate with nascent transcripts in a nuclear protein NXF1-dependent manner (PubMed:18936162) . In vitro, binds to RNA homopolymer; preferentially on poly (G) and to a lesser extent on poly (U), but not on poly (A) or poly (C) (PubMed:7688265, PubMed:7781595, PubMed:12950170, PubMed:15381419, PubMed:8156595) . Moreover, plays a role in the modulation of the sodium-activated potassium channel KCNT1 gating activity (PubMed:20512134) . Negatively regulates the voltage-dependent calcium channel current density in soma and presynaptic terminals of dorsal root ganglion (DRG) neurons, and hence regulates synaptic vesicle exocytosis (By similarity) . Modulates the voltage-dependent calcium channel CACNA1B expression at the plasma membrane by targeting the channels for proteosomal degradation (By similarity) . Plays a role in regulation of MAP1B- dependent microtubule dynamics during neuronal development (By similarity) . Recently, has been shown to play a translation- independent role in the modulation of presynaptic action potential (AP) duration and neurotransmitter release via large-conductance calcium-activated potassium (BK) channels in hippocampal and cortical excitatory neurons (PubMed:25561520) . Finally, FMR1 may be involved in the control of DNA damage response (DDR) mechanisms through the regulation of ATR-dependent signaling pathways such as histone H2AFX/H2A.x and BRCA1 phosphorylations (PubMed:24813610) .