Mutation of CRYAB encoding a conserved mitochondrial chaperone and antiapoptotic protein causes hereditary optic atrophy.

The degeneration of retinal ganglion cells (RGC) due to mitochondrial dysfunctions manifests optic neuropathy. However, the molecular components of RGC linked to optic neuropathy manifestations remain largely unknown. Here, we identified a potentially novel optic atrophy-causative CRYAB gene encoding a highly conserved major lens protein acting as mitochondrial chaperone and possessing antiapoptotic activities.

Daughter cell fate choice instructed preemptively by mother cells facing nutrient limitation.

Nutrients are vital to cellular activities, yet it is largely unknown how individual cells respond to nutrient deprivation. Live imaging results show that unlike the removal of amino acids or glutamine that immediately halts cell cycle progression, glucose withdrawal does not prevent cells from completing their current cycle. Although cells that begin to experience glucose withdrawal in S phase give rise to daughter cells with an equal choice of proliferation or quiescence, those enduring such experience in G1 phase give rise to daughter cells that predominantly enter quiescence.

Mitochondrial tRNA mutations in 887 Chinese subjects with hearing loss.

Mutations in the mitochondrial tRNAs have been reported to be the important cause of hearing loss. However, only a few cases have been identified thus far and the prevalence of mitochondrial tRNA mutations in hearing-impaired patients remain unclear. Here we performed the mutational analysis of 22 mitochondrial tRNA genes in a large cohort of 887 Han Chinese subjects with hearing loss by Sanger sequencing.

Contribution of mitochondrial ND1 3394T>C mutation to the phenotypic manifestation of Leber's hereditary optic neuropathy.

Mitochondrial DNA (mtDNA) mutations have been associated with Leber's hereditary optic neuropathy (LHON) and their pathophysiology remains poorly understood. In this study, we investigated the pathophysiology of a LHON susceptibility allele (m.3394T>C, p.

Leber's hereditary optic neuropathy is potentially associated with a novel m.5587T>C mutation in two pedigrees.

Mitochondrial (mt)DNA mutations have been revealed to be associated with Leber's hereditary optic neuropathy (LHON). The present study conducted clinical, genetic and molecular evaluations of two Han Chinese families. A total of 4 (3 men and 1 female) out of 14 matrilineal relatives in the families exhibited visual impairment with variable severity and age of onset.

Prevalence of Mitochondrial ND4 Mutations in 1281 Han Chinese Subjects With Leber's Hereditary Optic Neuropathy.

Purpose: To investigate the prevalence and spectrum of mitochondrial ND4 mutations in subjects with Leber's hereditary optic neuropathy (LHON).

Methods: A cohort of 1281 Chinese Han probands and 478 control subjects underwent clinical and genetic evaluation, and sequence analysis of mitochondrial (mt) DNA, as well as enzymatic assay of NADH:ubiquinone oxidoreductase.

Results: In this cohort, 503 probands had a family history of optic neuropathy and 778 subjects were sporadic cases.

GJB2 Mutation Spectrum and Genotype-Phenotype Correlation in 1067 Han Chinese Subjects with Non-Syndromic Hearing Loss.

Mutations in Gap Junction Beta 2 (GJB2) have been reported to be a major cause of non-syndromic hearing loss in many populations worldwide. The spectrums and frequencies of GJB2 variants vary substantially among different ethnic groups, and the genotypes among these populations remain poorly understood. In the present study, we carried out a systematic and extended mutational screening of GJB2 gene in 1067 Han Chinese subjects with non-syndromic hearing loss, and the resultant GJB2 variants were evaluated by phylogenetic, structural and bioinformatic analysis.

Mitochondrial tRNA(Ser(UCN)) variants in 2651 Han Chinese subjects with hearing loss.

Mutations in the mitochondrial DNA have been associated with hearing loss. However, the prevalence and spectrum of mitochondrial tRNA mutations in hearing-impaired subjects are poorly understood. In this report, we have investigated the prevalence and spectrum of mitochondrial tRNA(Ser(UCN)) mutations in a large cohort of 2651 Han Chinese subjects with hearing loss.

[Mitochondrial tRNA(Thr)T15943C mutation may be a new position that affects the phenotypic expression of deafness associated 12s rRNA A1555G mutation].

Objective: To identify secondary mutations associated with deafness in a Chinese family affected with deafness.

Methods: The family has been subjected to clinical and molecular analyses, in addition with measurement of reactive oxygen species and doubling time after establishment of immortalized lymphocyte cell lines.

Results: The results showed that the hearing loss level and audiometric configuration were discrepant among the family members with maternally transmitted hearing loss.