The Tousled-like kinases 1 and 2 (TLK1/TLK2) regulate DNA replication, repair and chromatin maintenance. TLK2 variants underlie the neurodevelopmental disorder (NDD) 'Intellectual Disability, Autosomal Dominant 57' (MRD57), characterized by intellectual disability and microcephaly. Several TLK1 variants have been reported in NDDs but their functional significance is unknown.
View Article and Find Full Text PDFBackground: The Tousled-like kinases 1 and 2 (TLK1/TLK2) regulate DNA replication, repair and chromatin maintenance. TLK2 variants are associated with 'Intellectual Disability, Autosomal Dominant 57' (MRD57), a neurodevelopmental disorder (NDD) characterized by intellectual disability (ID), autism spectrum disorder (ASD) and microcephaly. Several TLK1 variants have been reported in NDDs but their functional significance is unknown.
View Article and Find Full Text PDFThe human transcriptome contains thousands of small open reading frames (sORFs) that encode microproteins whose functions remain largely unexplored. Here, we show that TINCR lncRNA encodes pTINCR, an evolutionary conserved ubiquitin-like protein (UBL) expressed in many epithelia and upregulated upon differentiation and under cellular stress. By gain- and loss-of-function studies, we demonstrate that pTINCR is a key inducer of epithelial differentiation in vitro and in vivo.
View Article and Find Full Text PDFMicrotubules that assemble the mitotic spindle are generated by centrosomal nucleation, chromatin-mediated nucleation, and nucleation from the surface of other microtubules mediated by the augmin complex. Impairment of centrosomal nucleation in apical progenitors of the developing mouse brain induces p53-dependent apoptosis and causes non-lethal microcephaly. Whether disruption of non-centrosomal nucleation has similar effects is unclear.
View Article and Find Full Text PDFThe regulation of chromatin structure is critical for a wide range of essential cellular processes. The Tousled-like kinases, TLK1 and TLK2, regulate ASF1, a histone H3/H4 chaperone, and likely other substrates, and their activity has been implicated in transcription, DNA replication, DNA repair, RNA interference, cell cycle progression, viral latency, chromosome segregation and mitosis. However, little is known about the functions of TLK activity in vivo or the relative functions of the highly similar TLK1 and TLK2 in any cell type.
View Article and Find Full Text PDFDevelopment of brain edema in acute liver failure can increase intracranial pressure, which is a severe complication of the disease. However, brain edema is neither entirely cytotoxic nor vasogenic and the specific action of the brain microvasculature is still unknown. We aimed to analyze gene expression of brain cortex microvessels in two rat models of acute liver failure.
View Article and Find Full Text PDFThe generation of multiciliated cells (MCCs) is required for the proper function of many tissues, including the respiratory tract, brain, and germline. Defects in MCC development have been demonstrated to cause a subclass of mucociliary clearance disorders termed reduced generation of multiple motile cilia (RGMC). To date, only two genes, Multicilin (MCIDAS) and cyclin O (CCNO) have been identified in this disorder in humans.
View Article and Find Full Text PDFThe maintenance of genome stability is critical for the suppression of diverse human pathologies that include developmental disorders, premature aging, infertility and predisposition to cancer. The DNA damage response (DDR) orchestrates the appropriate cellular responses following the detection of lesions to prevent genomic instability. The MRE11 complex is a sensor of DNA double strand breaks (DSBs) and plays key roles in multiple aspects of the DDR, including DNA end resection that is critical for signaling and DNA repair.
View Article and Find Full Text PDFCEP63 is a centrosomal protein that facilitates centriole duplication and is regulated by the DNA damage response. Mutations in CEP63 cause Seckel syndrome, a human disease characterized by microcephaly and dwarfism. Here we demonstrate that Cep63-deficient mice recapitulate Seckel syndrome pathology.
View Article and Find Full Text PDFIn 2001, we reported linkage of an autosomal dominant form of limb-girdle muscular dystrophy, limb-girdle muscular dystrophy 1F, to chromosome 7q32.1-32.2, but the identity of the mutant gene was elusive.
View Article and Find Full Text PDFMitochondrial diseases are clinically and genetically heterogeneous disorders due to primary mutations in mitochondrial DNA (mtDNA) or nuclear DNA (nDNA). We studied a male infant with severe congenital encephalopathy, peripheral neuropathy, and myopathy. The patient's lactic acidosis and biochemical defects of respiratory chain complexes I, III, and IV in muscle indicated that he had a mitochondrial disorder while parental consanguinity suggested autosomal recessive inheritance.
View Article and Find Full Text PDFNavajo neurohepatopathy (NNH) is an autosomal recessive disease that is prevalent among Navajo children in the southwestern United States. The major clinical features are hepatopathy, peripheral neuropathy, corneal anesthesia and scarring, acral mutilation, cerebral leukoencephalopathy, failure to thrive, and recurrent metabolic acidosis with intercurrent infections. Infantile, childhood, and classic forms of NNH have been described.
View Article and Find Full Text PDFPyrophosphatases (PPases) catalyze the hydrolysis of inorganic pyrophosphate generated in several cellular enzymatic reactions. A novel human pyrophosphatase cDNA encoding a 334-amino-acid protein approximately 60% identical to the previously identified human cytosolic PPase was cloned and characterized. The novel enzyme, named PPase-2, was enzymatically active and catalyzed hydrolysis of pyrophosphate at a rate similar to that of the previously identified PPase-1.
View Article and Find Full Text PDFBackground. - We have established proliferating human cardiomyocyte cell lines derived from non-proliferating primary cultures of adult ventricular heart tissue, using a novel method that may be applicable to many post-mitotic primary cultures. Methods and results.
View Article and Find Full Text PDFLinezolid, an oxazolidinone antibiotic, inhibits bacterial protein synthesis by binding to 23S ribosomal RNA (rRNA). We studied 3 patients who experienced lactic acidosis while receiving linezolid therapy. The toxicity may have been caused by linezolid binding to mitochondrial 16S rRNA.
View Article and Find Full Text PDFBackground/aim: Alport syndrome is a hereditary glomerulonephritis, X-linked in 85% of the cases. This form is associated with mutations in the COL4A5 gene which encodes the alpha5 chain of type IV collagen. We have performed the mutational analysis of the COL4A5 gene in a Spanish family with X-linked Alport syndrome.
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