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Adams–Oliver Syndrome
Adams–Oliver syndrome (AOS) is a rare congenital disorder characterized by defects of the scalp and cranium (cutis aplasia congenita), transverse defects of the limbs, and mottling of the skin. Signs and symptoms Two key features of AOS are aplasia cutis congenita with or without underlying bony defects and terminal transverse limb defects. Cutis aplasia congenita is defined as missing skin over any area of the body at birth; in AOS skin aplasia occurs at the vertex of the skull. The size of the lesion is variable and may range from solitary round hairless patches to complete exposure of the cranial contents. There are also varying degrees of terminal limb defects (for example, shortened digits) of the upper extremities, lower extremities, or both. Individuals with AOS may have mild growth deficiency, with height in the low-normal percentiles. The skin is frequently observed to have a mottled appearance (cutis marmorata telangiectatica congenita). Other congenital anomalies, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital Disorder
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth defects are divided into two main types: structural disorders in which problems are seen with the shape of a body part and functional disorders in which problems exist with how a body part works. Functional disorders include metabolic and degenerative disorders. Some birth defects include both structural and functional disorders. Birth defects may result from genetic or chromosomal disorders, exposure to certain medications or chemicals, or certain infections during pregnancy. Risk factors include folate deficiency, drinking alcohol or smoking during pregnancy, poorly controlled diabetes, and a mother over the age of 35 years old. Many are believed to involve multiple factors. Birth defects may be vi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expressivity (genetics)
In genetics, expressivity is the degree to which a phenotype is expressed by individuals having a particular genotype. (Alternately, it may refer to the expression of particular gene by individuals having a certain phenotype.) Expressivity is related to the ''intensity'' of a given phenotype; it differs from penetrance, which refers to the ''proportion'' of individuals with a particular genotype that actually express the phenotype. Variable expressivity Variable expressivity refers to the degree in which a genotype is phenotypically expressed. For example, multiple people with the same disease can have the same genotype but one may express more severe symptoms, while another carrier may appear normal. This variation in expression can be affected by modifier genes, epigenetic factors or the environment. Modifier genes can alter the expression of other genes in either an additive or multiplicative way. Meaning the phenotype that is observed can be a result of two different alleles b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guanine Nucleotide Exchange Factor
Guanine nucleotide exchange factors (GEFs) are proteins or protein domains that activate monomeric GTPases by stimulating the release of guanosine diphosphate (GDP) to allow binding of guanosine triphosphate (GTP). A variety of unrelated structural domains have been shown to exhibit guanine nucleotide exchange activity. Some GEFs can activate multiple GTPases while others are specific to a single GTPase. Function Guanine nucleotide exchange factors (GEFs) are proteins or protein domains involved in the activation of small GTPases. Small GTPases act as molecular switches in intracellular signaling pathways and have many downstream targets. The most well-known GTPases comprise the Ras superfamily and are involved in essential cell processes such as cell differentiation and proliferation, cytoskeletal organization, vesicle trafficking, and nuclear transport. GTPases are active when bound to GTP and inactive when bound to GDP, allowing their activity to be regulated by GEFs and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GTPase-activating Protein
GTPase-activating proteins or GTPase-accelerating proteins (GAPs) are a family of regulatory proteins whose members can bind to activated G proteins and stimulate their GTPase activity, with the result of terminating the signaling event. GAPs are also known as RGS protein, or RGS proteins,Kimple, A.J. "Structural Determinants of G-protein α Subunit Selectivity by Regulator of G-protein Signaling 2 (RGS2)". ''The Journal of Biological Chemistry''. 284 (2009): 19402-19411. and these proteins are crucial in controlling the activity of G proteins. Regulation of G proteins is important because these proteins are involved in a variety of important cellular processes. The large G proteins, for example, are involved in transduction of signaling from the G protein-coupled receptor for a variety of signaling processes like hormonal signaling, and small G proteins are involved in processes like cellular trafficking and cell cycling. GAP's role in this function is to turn the G protein's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rho Family Of GTPases
The Rho family of GTPases is a family of small (~21 kDa) signaling G proteins, and is a subfamily of the Ras superfamily. The members of the Rho GTPase family have been shown to regulate many aspects of intracellular actin dynamics, and are found in all eukaryotic kingdoms, including yeasts and some plants. Three members of the family have been studied in detail: Cdc42, Rac1, and RhoA. All G proteins are "molecular switches", and Rho proteins play a role in organelle development, cytoskeletal dynamics, cell movement, and other common cellular functions. History Identification of the Rho family of GTPases began in the mid-1980s. The first identified Rho member was RhoA, isolated serendipitously in 1985 from a low stringency cDNA screening. Rac1 and Rac2 were identified next, in 1989 followed by Cdc42 in 1990. Eight additional mammalian Rho members were identified from biological screenings until the late 1990s, a turning point in biology where availability of complete genome seq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DLL4
Delta-like 4 is a protein that in humans is encoded by the ''DLL4'' gene. This gene is a homolog of the Drosophila delta gene. The delta gene family encodes Notch ligands that are characterized by a DSL domain, EGF repeats, and a transmembrane A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequentl ... domain. References Further reading * * * * * * * * * * * * * * * * External links * {{gene-15-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notch 1
Neurogenic locus notch homolog protein 1 (Notch 1) is a protein encoded in humans by the ''NOTCH1'' gene. Notch 1 is a single-pass transmembrane receptor. Function This gene encodes a member of the Notch family. Members of this Type 1 transmembrane protein family share structural characteristics including an extracellular domain consisting of multiple epidermal growth factor-like (EGF) repeats, and an intracellular domain consisting of multiple, different domain types. Notch family members play a role in a variety of developmental processes by controlling cell fate decisions. The Notch signaling network is an evolutionarily conserved intercellular signaling pathway that regulates interactions between physically adjacent cells. In ''Drosophila'', notch interaction with its cell-bound ligands (delta, serrate) establishes an intercellular signaling pathway that plays a key role in development. Homologues of the notch-ligands have also been identified in humans, but precise interac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBPJ
Recombination signal binding protein for immunoglobulin kappa J region is a protein that in humans is encoded by the ''RBPJ'' gene. RBPJ also known as CBF1, is the human homolog for the Drosophila gene Suppressor of Hairless. Its promoter region is classically used to demonstrate Notch1 signaling. Interactions RBPJ has been shown to interact with: * NOTCH1 * NCOR2, * PCAF, * SND1, * SNW1, and *SOX18 Transcription factor SOX-18 is a protein that in humans is encoded by the ''SOX18'' gene. Function This gene encodes a member of the SOX (SRY-related HMG-box) family of transcription factors involved in the regulation of embryonic development .... References Further reading * * * * * * * * * * * * * * * * * External links * {{NLM content Transcription factors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DOCK6
Dock6 (Dedicator of cytokinesis 6), also known as Zir1 is a large (~200 kDa) protein involved in intracellular signalling networks. It is a member of the DOCK-C subfamily of the DOCK family of guanine nucleotide exchange factors which function as activators of small G proteins. Discovery Dock6 was identified as one of a family of proteins which share high sequence similarity with Dock180, the archetypal member of the DOCK family. It has a similar domain arrangement to other DOCK proteins, with a DHR1 domain known in other proteins to bind phospholipids, and a DHR2 domain containing the GEF activity. Function There is currently very little information about the cellular role of this protein. However, Dock6 has been reported to exhibit dual GEF specificity towards the small G proteins Rac1 and Cdc42. It is the only DOCK family member reported to activate both of these G proteins. The same study also showed that transfection of the Dock6 DHR2 domain into N1E-115 neuroblastoma c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARHGAP31
The Rho GTPase activating protein 31 is encoded in humans by the ''ARHGAP31'' gene. It is a Cdc42/ Rac1 GTPase regulator. Function ARHGAP31 encodes a GTPase-activating protein (GAP). A variety of cellular processes are regulated by Rho GTPases which cycle between an inactive form bound to GDP and an active form bound to GTP. This cycling between inactive and active forms is regulated by guanine nucleotide exchange factors and GAPs. The encoded protein is a GAP shown to regulate two GTPases involved in protein trafficking and cell growth. Clinical relevance ARHGAP31 mutations result in a loss of available active Cdc42 and consequently disrupt actin cytoskeletal The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is compo ... structures, causing syndromic cutis aplasia and limb anomalies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
