Table 6 of Mansergh, Mol Vis 2015; 21:61-87.


Table 6. Functions of selected genes also identified in other retinal array studies.

Gene Title and symbol Functions Retinal functions References
betacellulin, epidermal growth factor family member Btc Member of the EGF family of growth factors, synthesized primarily as a transmembrane precursor, which is then processed to mature molecule by proteolytic events. This protein is a ligand for the EGF receptor. Involved in propagating luteinizing hormone signalling through the ovary during ovulation. Constituent of bone marrow stem cell conditioned medium (BMSC medium), BMSC medium treated RPCs are more likely to favour neural differentiation.May also enhance RPC proliferation. Overexpressed in diabetic mice, may contribute to increased vascular permeability and vascular oedema, leading to diabetic retinopathy. Gene ID:685. OMIM 600345 [63,64].
synaptosomal-associated protein 25 Snap25 Snap25 is a presynaptic plasma membrane protein involved in the regulation of neurotransmitter release. Neuronal exocytosis requires 3 SNARE proteins: synaptobrevin on the synaptic vesicle, and syntaxin and SNAP25 on the plasma membrane. Expressed in ribbon synapses from pn4, may be involved in their organization. Strongly expressed in horizontal cells. Thought to play role in photoreceptor development. Expressed in the Golgi complex of retinal neurons as well as involvement in synaptic vesicle release. It is located in the perinuclear compartment of retinal neurons Gene ID: 6616, OMIM 600322 [65-67],
complexin 4 Cplx4 Probable member of the complexin family, may be involved in synaptic vesicle exocytosis. Contains a C-terminal CAAX box motif for posttranslational prenylation. Expression is retinal specific, or restricted to eye and retina (databases). Expression seems to be localized to rod photoreceptor ribbon synapses. Positive regulator of synaptic transmission in mouse hippocampal neurons. Present in IPL and bipolar cell synapses. Double Cplx3/4 KO mice show behavioural responses suggestive of visual deficit and disordered ribbon synapses. Ganglion cell ON and OFF synapses also affected differentially. Essential regulators of neurotransmission at retinal ribbon synapses. Gene ID:339302 OMIM609586 [68,69].
podocalyxin-like Podxl Member of the sialomucin protein family. Important component of glomerular podocytes. Other biological activities include binding in a membrane protein complex with Na+/H+ exchanger regulatory factor to intracellular cytoskeletal elements, playing a role in hematopoetic cell differentiation, and being expressed in vascular endothelium cells and L-selectin binding. Highest expression in kidney, pancreas and heart. Linked to ezrin and the actin cytoskeleton via Nherf2. Identified via array as a marker of early rod precursors which are capable of integrating into recipient retinas after transplantation. [31] Gene ID: 5420. OMIM602632.
calsyntenin 1 Clstn1 Isolated from brain cDNA library, expressed by >90% of neurons. Localized in post-synaptic membrane. Signalling may be by proteolytic cleavage. Expression raised in Alzheimers and Parkinsons samples decreased in neuroblastoma. Localized in organelles alongside microtubules, partially co-localized with kinesin. Organelles transported in a manner consistent with fast axonal transport. Unknown Gene ID: 22883 OMIM611321 [70,71]
cholinergic receptor, nicotinic, alpha polypeptide 5 Chrna5 Nicotinic acetylcholine receptor subunit and a member of a superfamily of ligand-gated ion channels that mediate fast signal transmission at synapses. Defects in this gene have been linked to susceptibility to lung cancer type 2 (LNCR2), variants are associated with increased risk of nicotine addiction, a propensity shared with Chrna5 knockout mice. Evolution of this gene in primates has been faster than would be expected by chance, may be involved in the evolution of larger brains in humans. Unknown Gene ID: 1138. OMIM118505 [72,73].