IQSEC2: Difference between revisions

From WikiMD's Wellness Encyclopedia

CSV import
Tags: mobile edit mobile web edit
 
CSV import
 
(3 intermediate revisions by the same user not shown)
Line 1: Line 1:
{{Infobox_gene}}
{{Short description|IQSEC2 gene and its role in human health}}
'''IQ motif and Sec7 domain 2''' is a [[protein]] that in humans is encoded by the ''IQSEC2'' [[gene]].<ref name="entrez">{{cite web | title = Entrez Gene: IQ motif and Sec7 domain 2| url = https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=23096| accessdate = }}</ref><ref name="pmid9628581">{{cite journal |vauthors=Nagase T, Ishikawa K, Miyajima N, Tanaka A, Kotani H, Nomura N, Ohara O | title = Prediction of the coding sequences of unidentified human genes. IX. The complete sequences of 100 new cDNA clones from brain which can code for large proteins in vitro | journal = DNA Res. | volume = 5 | issue = 1 | pages = 31–9 |date=February 1998 | pmid = 9628581 | doi = 10.1093/dnares/5.1.31| url = | issn = | doi-access = free }}</ref>


== Function ==
'''IQSEC2''' is a gene that encodes a protein involved in intracellular signaling pathways. This protein is part of the IQ motif and Sec7 domain-containing protein family, which plays a crucial role in the regulation of [[GTPase]] activity. Mutations in the IQSEC2 gene have been associated with various neurological disorders, including [[intellectual disability]] and [[epilepsy]].


The IQSEC2 gene encodes a [[guanine nucleotide exchange factor]] for the ARF family of [[G protein|GTP-binding protein]]s (see for example [[ARF1]]).<ref name="pmid20473311">{{cite journal |vauthors=Shoubridge C, Tarpey PS, Abidi F, Ramsden SL, Rujirabanjerd S, Murphy JA, Boyle J, Shaw M, Gardner A, Proos A, Puusepp H, Raymond FL, Schwartz CE, Stevenson RE, Turner G, Field M, Walikonis RS, Harvey RJ, Hackett A, Futreal PA, Stratton MR, Gécz J | title = Mutations in the guanine nucleotide exchange factor gene IQSEC2 cause nonsyndromic intellectual disability | journal = Nat. Genet. | volume = 42 | issue = 6 | pages = 486–8 |date=June 2010 | pmid = 20473311 | doi = 10.1038/ng.588 | url = | issn = | pmc = 3632837 }}</ref>
==Structure==
The IQSEC2 gene is located on the X chromosome at the Xp11.22 locus. It spans approximately 200 kilobases and consists of multiple exons. The protein encoded by IQSEC2 contains several important domains, including the IQ motif, which is involved in [[calmodulin]] binding, and the Sec7 domain, which is crucial for its function as a [[guanine nucleotide exchange factor]] (GEF).


== Clinical significance ==
==Function==
The primary function of the IQSEC2 protein is to act as a GEF for the ADP-ribosylation factor (ARF) family of GTPases. These GTPases are involved in various cellular processes, including [[vesicle trafficking]], [[cytoskeleton]] organization, and [[signal transduction]]. By facilitating the exchange of GDP for GTP on ARF proteins, IQSEC2 regulates their activity and, consequently, the downstream signaling pathways.


It is associated with [[X-Linked mental retardation]] 1.<ref name="pmid20473311"/>
==Clinical Significance==
Mutations in the IQSEC2 gene have been linked to a spectrum of neurodevelopmental disorders. These include:


==References==
* '''Intellectual Disability''': IQSEC2 mutations are a known cause of X-linked intellectual disability. Affected individuals may exhibit a range of cognitive impairments, from mild to severe.
{{reflist}}


==Further reading==
* '''Epilepsy''': Some patients with IQSEC2 mutations experience [[seizures]] and are diagnosed with epilepsy. The severity and type of seizures can vary widely among individuals.
{{refbegin | 2}}
*{{cite journal  |vauthors=Ross MT, Grafham DV, Coffey AJ, etal |title=The DNA sequence of the human X chromosome. |journal=Nature |volume=434 |issue= 7031 |pages= 325–37 |year= 2005 |pmid= 15772651 |doi= 10.1038/nature03440 |pmc=2665286|bibcode=2005Natur.434..325R }}
*{{cite journal  |vauthors=Ota T, Suzuki Y, Nishikawa T, etal |title=Complete sequencing and characterization of 21,243 full-length human cDNAs. |journal=Nat. Genet. |volume=36 |issue= 1 |pages= 40–5 |year= 2004 |pmid= 14702039 |doi= 10.1038/ng1285 |doi-access= free }}
*{{cite journal  |vauthors=Filippova GN, Cheng MK, Moore JM, etal |title=Boundaries between chromosomal domains of X inactivation and escape bind CTCF and lack CpG methylation during early development. |journal=Dev. Cell |volume=8 |issue= 1 |pages= 31–42 |year= 2005 |pmid= 15669143 |doi=  10.1016/j.devcel.2004.10.018}}
*{{cite journal  |vauthors=Cox R, Mason-Gamer RJ, Jackson CL, Segev N |title=Phylogenetic analysis of Sec7-domain-containing Arf nucleotide exchangers. |journal=Mol. Biol. Cell |volume=15 |issue= 4 |pages= 1487–505 |year= 2004 |pmid= 14742722 |doi= 10.1091/mbc.E03-06-0443 |pmc=379250}}
*{{cite journal  |vauthors=Dosemeci A, Makusky AJ, Jankowska-Stephens E, etal |title=Composition of the synaptic PSD-95 complex. |journal=Mol. Cell. Proteomics |volume=6 |issue= 10 |pages= 1749–60 |year= 2007 |pmid= 17623647 |doi= 10.1074/mcp.M700040-MCP200 |pmc=2096750}}
*{{cite journal  |vauthors=Tsuchiya KD, Greally JM, Yi Y, etal |title=Comparative sequence and x-inactivation analyses of a domain of escape in human xp11.2 and the conserved segment in mouse. |journal=Genome Res. |volume=14 |issue= 7 |pages= 1275–84 |year= 2004 |pmid= 15197169 |doi= 10.1101/gr.2575904 |pmc=442142}}
*{{cite journal  |vauthors=Strausberg RL, Feingold EA, Grouse LH, etal |title=Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=99 |issue= 26 |pages= 16899–903 |year= 2002 |pmid= 12477932 |doi= 10.1073/pnas.242603899 |pmc=139241|bibcode=2002PNAS...9916899M }}
*{{cite journal  |vauthors=Barbe L, Lundberg E, Oksvold P, etal |title=Toward a confocal subcellular atlas of the human proteome. |journal=Mol. Cell. Proteomics |volume=7 |issue= 3 |pages= 499–508 |year= 2008 |pmid= 18029348 |doi= 10.1074/mcp.M700325-MCP200 |doi-access= free }}
*{{cite journal  |vauthors=Murphy JA, Jensen ON, Walikonis RS |title=BRAG1, a Sec7 domain-containing protein, is a component of the postsynaptic density of excitatory synapses. |journal=Brain Res. |volume=1120 |issue= 1 |pages= 35–45 |year= 2006 |pmid= 17045249 |doi= 10.1016/j.brainres.2006.08.096 }}
{{refend}}


{{GTP-binding protein regulators}}
* '''Autism Spectrum Disorder''': There is evidence to suggest that mutations in IQSEC2 may contribute to the development of [[autism spectrum disorder]] in some cases.


[[Category:Human proteins]]
==Pathophysiology==
The exact mechanisms by which IQSEC2 mutations lead to neurological disorders are not fully understood. However, it is believed that the disruption of ARF-mediated signaling pathways plays a critical role. The loss of proper GTPase regulation can affect synaptic function and neuronal connectivity, leading to the observed clinical phenotypes.


==Research Directions==
Ongoing research is focused on understanding the precise molecular mechanisms by which IQSEC2 mutations cause disease. Animal models and cellular studies are being used to explore the role of IQSEC2 in neuronal development and function. Additionally, there is interest in developing targeted therapies that can modulate the activity of the IQSEC2 protein or its downstream signaling pathways.


{{gene-X-stub}}
==Related pages==
{{dictionary-stub1}}
* [[GTPase]]
* [[Intellectual disability]]
* [[Epilepsy]]
* [[Autism spectrum disorder]]
* [[Calmodulin]]
 
[[Category:Genes on human chromosome X]]
[[Category:Neurodevelopmental disorders]]

Latest revision as of 19:26, 22 March 2025

IQSEC2 gene and its role in human health


IQSEC2 is a gene that encodes a protein involved in intracellular signaling pathways. This protein is part of the IQ motif and Sec7 domain-containing protein family, which plays a crucial role in the regulation of GTPase activity. Mutations in the IQSEC2 gene have been associated with various neurological disorders, including intellectual disability and epilepsy.

Structure[edit]

The IQSEC2 gene is located on the X chromosome at the Xp11.22 locus. It spans approximately 200 kilobases and consists of multiple exons. The protein encoded by IQSEC2 contains several important domains, including the IQ motif, which is involved in calmodulin binding, and the Sec7 domain, which is crucial for its function as a guanine nucleotide exchange factor (GEF).

Function[edit]

The primary function of the IQSEC2 protein is to act as a GEF for the ADP-ribosylation factor (ARF) family of GTPases. These GTPases are involved in various cellular processes, including vesicle trafficking, cytoskeleton organization, and signal transduction. By facilitating the exchange of GDP for GTP on ARF proteins, IQSEC2 regulates their activity and, consequently, the downstream signaling pathways.

Clinical Significance[edit]

Mutations in the IQSEC2 gene have been linked to a spectrum of neurodevelopmental disorders. These include:

  • Intellectual Disability: IQSEC2 mutations are a known cause of X-linked intellectual disability. Affected individuals may exhibit a range of cognitive impairments, from mild to severe.
  • Epilepsy: Some patients with IQSEC2 mutations experience seizures and are diagnosed with epilepsy. The severity and type of seizures can vary widely among individuals.
  • Autism Spectrum Disorder: There is evidence to suggest that mutations in IQSEC2 may contribute to the development of autism spectrum disorder in some cases.

Pathophysiology[edit]

The exact mechanisms by which IQSEC2 mutations lead to neurological disorders are not fully understood. However, it is believed that the disruption of ARF-mediated signaling pathways plays a critical role. The loss of proper GTPase regulation can affect synaptic function and neuronal connectivity, leading to the observed clinical phenotypes.

Research Directions[edit]

Ongoing research is focused on understanding the precise molecular mechanisms by which IQSEC2 mutations cause disease. Animal models and cellular studies are being used to explore the role of IQSEC2 in neuronal development and function. Additionally, there is interest in developing targeted therapies that can modulate the activity of the IQSEC2 protein or its downstream signaling pathways.

Related pages[edit]