Project description:<p>Combined Immunodeficiency with Multiple Intestinal Atresias (CID-MIA) is a rare genetic disorder with the cause previously unknown. Symptoms of CID-MIA include atresias in the small and/or large intestine, as well as immunodeficiency. In this study, we sequenced the whole exome of 5 unrelated CID-MIA patients as well as their healthy family members, and identified deleterious homozygous or compound heterozygous mutations in the gene <i>TTC7A</i> in all the 5 patients, as well as in 3 additional patients with Sanger sequencing. Our findings strongly indicate <i>TTC7A</i> dysfunction to be the cause for CID-MIA.</p>
Project description:<p>Combined Immunodeficiency with Multiple Intestinal Atresias (CID-MIA) is a rare genetic disorder with the cause previously unknown. Symptoms of CID-MIA include atresias in the small and/or large intestine, as well as immunodeficiency. In this study, we sequenced the whole exome of 5 unrelated CID-MIA patients as well as their healthy family members, and identified deleterious homozygous or compound heterozygous mutations in the gene <i>TTC7A</i> in all the 5 patients, as well as in 3 additional patients with Sanger sequencing. Our findings strongly indicate <i>TTC7A</i> dysfunction to be the cause for CID-MIA.</p>
Project description:Inherited TTC7A loss of function mutations causes intestinal and immune deficiency. TTC7A is expressed in hematopoietic and epithelial cells however its cellular function remains poorly understood. In this work we provided evidence that TTC7A is an intrinsic nucleus factor. In an attempt to link the function of TTC7A in chromatin compaction, histone modifications and general transcriptional regulation we undertook to map the observed interaction of TTC7A to chromatin genome-wide by ChiP-Seq of Flag-tagged WT_TTC7A expressed in B lymphoblastoid cell lines using two anti-Flag antibodies (hereafter IP-Flag1 and IP-Flag2).
Project description:Combined immunodeficiencies are a heterogeneous collection of primary immune disorders that exhibit defects in T cell development or function, along with impaired B cell activity even in light of normal B cell maturation. CARMIL2 (RLTPR) is a protein involved in cytoskeletal organization and cell migration which also plays a role in CD28 co-signaling of T cells. Mutations in this protein have recently been reported to cause a novel primary immunodeficiency disorder with variable phenotypic presentations. Here we deposit genotyping data for seven patients from three unrelated, consanguineous multiplex families that presented with dermatitis, eosophagitis and recurrent skin and chest infections with evidence of combined immunodeficiency. By using this genotyping data to perform autozygome-guided analysis, and coupling it with the results of whole exome sequencing, we uncovered two mutations not previously reported (p.R50T and p.L846Sfs) in CARMIL2.
Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
