Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

CUL4A and B encode subunits of E3-ubiquitin ligases implicated in diverse processes including nucleotide excision repair, regulating gene expression and controlling DNA replication fork licensing. But, the functional distinction between CUL4A and CUL4B, if any, is unclear. Recently, mutations in CUL4B were identified in humans associated with mental retardation, relative macrocephaly, tremor and a peripheral neuropathy. Cells from these patients offer a unique system to help define at the molecular level the consequences of defective CUL4B specifically. We show that these patient-derived cells exhibit sensitivity to camptothecin (CPT), impaired CPT-induced topoisomerase I (Topo I) degradation and ubiquitination, thereby suggesting Topo I to be a novel Cul4-dependent substrate. Consistent with this, we also find that these cells exhibit increased levels of CPT-induced DNA breaks. Furthermore, over-expression of known CUL4-dependent substrates including Cdt1 and p21 appear to be a feature of these patient-derived cells. Collectively, our findings highlight the interplay between CUL4A and CUL4B and provide insight into the pathogenesis of CUL4B-deficiency in humans.
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PMID:Mutations in Cullin 4B result in a human syndrome associated with increased camptothecin-induced topoisomerase I-dependent DNA breaks. 2006 23

CUL4B gene mutation can cause intelligence deficiency 15, a syndromic form of X-linked mental retardation characterized by severe intellectual deficit associated with short stature, craniofacial dysmorphism, speech delay and impairment, tremor and gait ataxia. Here, we generated iPSCs from a Chinese patient with c.1007_1011del (p.(Ile336fs)) in CUL4B gene by reprogramming peripheral blood mononuclear cells with non-integrating vectors. The generated iPSC line (SDQLCHi015-A) expresses pluripotency markers, presents a normal karyotype and is able to differentiate into three germ layers.
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PMID:Generation of an iPSC line (SDQLCHi015-A) from peripheral blood mononuclear cells of a patient with mental retardation type 15 carrying c.1007_1011del, p.(Ile336fs) in CUL4B gene. 3167 76