Functional analysis on sucrose transporters in sweet potato / 生物工程学报

Sweet potato is an important food crop that can also be used as an industrial raw material. Sucrose is the main form of long-distance carbohydrate transport in plants, and sucrose transporter (SUT) regulates the transmembrane transport and distribution of sucrose during plant growth and metabolism. Moreover, SUT plays a key role in phloem mediated source-to-sink sucrose transport and physiological activities, supplying sucrose for the sink tissues. In this study, the full-length cDNA sequences of IbSUT62788 and IbSUT81616 were obtained by rapid amplification of cDNA ends (RACE) cloning according to the transcripts of the two SUT coding genes which were differentially expressed in sweet potato storage roots with different starch properties. Phylogenetic analysis was performed to clarify the classification of IbSUT62788 and IbSUT81616. The subcellular localization of IbSUT62788 and IbSUT81616 was determined by transient expression in Nicotiana benthamiana. The function of IbSUT62788 and IbSUT81616 in sucrose and hexose absorption and transport was identified using yeast functional complementarity system. The expression pattern of IbSUT62788 and IbSUT81616 in sweet potato organs were analyzed by real-time fluorescence quantitative PCR (RT-qPCR). Arabidopsis plants heterologous expressing IbSUT62788 and IbSUT81616 genes were obtained using floral dip method. The differences in starch and sugar contents between transgenic and wild-type Arabidopsis were compared. The results showed IbSUT62788 and IbSUT81616 encoded SUT proteins with a length of 505 and 521 amino acids, respectively, and both proteins belonged to the SUT1 subfamily. IbSUT62788 and IbSUT81616 were located in the cell membrane and were able to transport sucrose, glucose and fructose in the yeast system. In addition, IbSUT62788 was also able to transport mannose. The expression of IbSUT62788 was higher in leaves, lateral branches and main stems, and the expression of IbSUT81616 was higher in lateral branches, stems and storage roots. After IbSUT62788 and IbSUT81616 were heterologously expressed in Arabidopsis, the plants grew normally, but the biomass increased. The heterologous expression of IbSUT62788 increased the soluble sugar content, leaf size and 1 000-seed weight of Arabidopsis plants. Heterologous expression of IbSUT81616 increased starch accumulation in leaves and root tips and 1 000-seed weight of seeds, but decreased soluble sugar content. The results obtained in this study showed that IbSUT62788 and IbSUT81616 might be important genes regulating sucrose and sugar content traits in sweet potato. They might carry out physiological functions on cell membrane, such as transmembrane transport of sucrose, sucrose into and out of sink tissue, as well as transport and unloading of sucrose into phloem. The changes in traits result from their heterologous expression in Arabidopsis indicates their potential in improving the yield of other plants or crops. The results obtained in this study provide important information for revealing the functions of IbSUT62788 and IbSUT81616 in starch and glucose metabolism and formation mechanism of important quality traits in sweet potato.

Clinical characteristics and genetic analysis of a case with adult neuronal ceroid lipofuscinosis type 7 due to variant of MFSD8 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics and genetic variants in a patient with adult ceroid lipofuscinosis neuronal type 7 (ACLN7).@*METHODS@#A female patient diagnosed with ACLN7 in Henan Provincial People's Hospital in June 2021 was selected as the study subject. Clinical data, auxiliary examination and result of genetic testing were retrospectively analyzed.@*RESULTS@#The patient, a 39-year-old female, has mainly presented progressive visual loss, epilepsy, cerebellar ataxia and mild cognitive decline. Neuroimaging analysis has revealed generalized brain atrophy, prominently cerebellum. Fundus photography has revealed retinitis pigmentosa. Ultrastructural skin examination has revealed granular lipofuscin deposits in the periglandular interstitial cells. Whole exome sequencing revealed that she has harbored compound heterozygous variants of the MSFD8 gene, namely c.1444C>T (p.R482*) and c.104G>A (p.R35Q). Among these, c.1444C>T (p.R482*) was a well established pathogenic variant, while c.104G>A (p.R35Q) was a missense variant unreported previously. Sanger sequencing confirmed that the daughter, son and elder brother of the proband have respectively carried heterozygous c.1444C>T (p.R482*), c.104G>A (p.R35Q), and c.104G>A (p.R35Q) variants of the same gene. The family has therefore fit with the autosomal recessive inheritance pattern of the CLN7.@*CONCLUSION@#Compared with previously reported cases, this patient has the latest onset of the disease with a non-lethal phenotype. Her clinical features have involved multiple systems. Cerebellar atrophy and fundus photography may be indicative of the diagnosis. The c.1444C>T (p.R482*) and c.104G>A (p.R35Q) compound heterozygous variants of the MFSD8 gene probably underlay the pathogenesis in this patient.

Clinical and molecular genetic analysis of Angelman syndrome with oculocutaneous albinism type 2: A case report and literature review / 北京大学学报(医学版)

To summarize the clinical diagnosis and treatment process and genetic test results and characteristics of one child with Angelman syndrome (AS) complicated with oculocutaneous albinism type 2 (OCA2), and to review the literature. "Angelman syndrome" "P gene" and "Oculocutaneous albinism type 2" were used as keywords to search at CNKI, Wanfang, and PubMed databases (from creation to December 2019). Then all the patients were analyzed. The patient in this study was a girl aged 1 year. After birth, she was found to present as white body, yellow hair, and nystagmus. She could raise her head at the age of 2 months and turn over at the age of 7 months. The head circumference was 42 cm and she could not sit alone or speak at present. Trio-based exome sequencing revealed that the patient carried a homozygous mutation of c.168del (p.Gln58ArgfsTer44) in the P gene, and her father was heterozygous and her mother was wild-type. The detection of copy number variation showed deletion on the maternal chromosome at 15q11.2-13.1 region (P gene located in this region) in the patient. Until December 2019, a total of 4 cases in the 4 literature had been reported. Adding our case here, the 5 cases were summarized and found that all the cases showed white skin, golden hair, and shallow iris after birth. Comprehensive developmental delay was found around 6 months of age after birth, and the language remained undeveloped in 2 cases till follow-up into childhood. Seizures occurred in 4 patients. Two cases had ataxia. All the 5 cases had acquired microcephaly. Two cases had a family history of albinism. Electroencephalogram monitoring was completed in 3 cases and the results were abnormal. Genetic tests showed that all the 5 cases had deletion on maternal chromosome at 15q11-13 region. Four cases carried mutation of P gene on paternal chromosome. And 1 case was clinically diagnosed as OCA2 without P gene test. AS combined with OCA2 is relatively rare. OCA2 is easily diagnosed based on the obvious clinical manifestations after birth. When combined with clinical manifestations such as neurodevelopmental delay, it might indicate the possibility of AS that is hardly diagnosed clinically at an early stage. Genetic tests can reveal the cross-genetic phenomenon of AS and OCA2 and the complex of them can be eventually diagnosed.

Fixation of pfcrt chloroquine resistance alleles in Plasmodium falciparum clinical isolates collected from unrest tribal agencies of Pakistan / Fixação de alelos de resistência à cloroquina pfcrt em isolados clínicos de Plasmodium falciparum coletados de agitações de agências tribais do Paquistão

Abstract Plasmodium falciparum resistance to Chloroquine (CQ) is a significant cause of mortality and morbidity worldwide. There is a paucity of documented data on the prevalence of CQ-resistant mutant haplotypes of Pfcrt and Pfmdr1 genes from malaria-endemic war effected Federally Administered Tribal Areas of Pakistan. The objective of this study was to investigate the prevalence of P. falciparum CQ-resistance in this area. Clinical isolates were collected between May 2017 and May 2018 from North Waziristan and South Waziristan agencies of Federally Administrated Trial Area. Subsequently, Giemsa-stained blood smears were examined to detect Plasmodium falciparum. Extraction of malarial DNA was done from microscopy positive P. falciparum samples, and P. falciparum infections were confirmed by nested PCR (targeting Plasmodium small subunit ribosomal ribonucleic acid (ssrRNA) genes). All PCR confirmed P. falciparum samples were sequenced by pyrosequencing to find out mutation in Pfcrt gene at codon K76T and in pfmdr1 at codons N86Y, Y184F, N1042D, and D1246Y. Out of 121 microscopies positive P. falciparum cases, 109 samples were positive for P. falciparum by nested PCR. Pfcrt K76T mutation was found in 96% of isolates, Pfmdr1 N86Y mutation was observed in 20%, and 11% harboured Y184F mutation. All samples were wild type for Pfmdr1 codon N1042D and D1246Y. In the FATA, Pakistan, the frequency of resistant allele 76T remained high despite the removal of CQ. However, current findings of the study suggest complete fixation of P. falciparum CQ-resistant genotype in the study area.

Resumo A resistência do Plasmodium falciparum à cloroquina (CQ) é uma causa significativa de mortalidade e morbidade em todo o mundo. Há uma escassez de dados documentados sobre a prevalência de haplótipos mutantes CQ-resistentes dos genes Pfcrt e Pfmdr1 da guerra endêmica da malária em áreas tribais administradas pelo governo federal do Paquistão. O objetivo deste estudo foi investigar a prevalência de resistência a CQ de P. falciparum nesta área. Isolados clínicos foram coletados entre maio de 2017 e maio de 2018 nas agências do Waziristão do Norte e do Waziristão do Sul da Área de Ensaio Administrada Federalmente. Posteriormente, esfregaços de sangue corados com Giemsa foram examinados para detectar Plasmodium falciparum. A extração do DNA da malária foi feita a partir de amostras de P. falciparum positivas para microscopia, e as infecções por P. falciparum foram confirmadas por nested PCR (visando genes de ácido ribonucleico ribossômico de subunidade pequena de Plasmodium (ssrRNA)). Todas as amostras de P. falciparum confirmadas por PCR foram sequenciadas por pirosequenciamento para descobrir a mutação no gene Pfcrt no códon K76T e em pfmdr1 nos códons N86Y, Y184F, N1042D e D1246Y. De 121 microscopias de casos positivos de P. falciparum, 109 amostras foram positivas para P. falciparum por nested PCR. A mutação Pfcrt K76T foi encontrada em 96% dos isolados, a mutação Pfmdr1 N86Y foi observada em 20% e 11% abrigou a mutação Y184F. Todas as amostras eram do tipo selvagem para o códon N1042D e D1246Y de Pfmdr1. No FATA, Paquistão, a frequência do alelo resistente 76T permaneceu alta apesar da remoção de CQ. No entanto, as descobertas atuais do estudo sugerem a fixação completa do genótipo resistente a CQ de P. falciparum na área de estudo.

Genetic testing and prenatal diagnosis for thirteen Chinese pedigrees affected with oculocutaneous albinism / 中华医学遗传学杂志

OBJECTIVE@#To identify the causative variants in 13 Chinese pedigrees affected with oculocutaneous albinism (OCA) so as to provide genetic counseling and prenatal diagnosis to them.@*METHODS@#Thirteen unrelated pedigrees with clinically diagnosed OCA were collected and classified based on the manifestation of skin and eyes. With informed consent obtained from the participants, peripheral blood samples were collected from the probands and their family members for the extraction of genomic DNA. Candidate variants were screened by targeted capture and next generation sequencing, and the results were validated by Sanger sequencing. Prenatal diagnosis was provided to the families upon their subsequent pregnancies.@*RESULTS@#Causative variants were detected in all probands, including 10 with compound heterozygotes or homozygotes for TYR gene variants and 3 with compound heterozygotes for OCA2 gene variants. Among these, two variants [TYR: c.650G>C (p.Arg217Pro) and OCA2: c.516-2A>T] were unreported previously. The pathogenicity of the novel TYR: c.650G>C (p.Arg217Pro) variant was verified through bioinformatic analysis and prediction of three dimensional structure of the protein. Prenatal diagnosis was provided to 6 fetuses with a high risk for OCA. Four fetuses were found to be carriers, one did not carry the variants of the proband, and one was affected with OCA.@*CONCLUSION@#Identification of the pathogenic variants in the 13 probands, including 2 novel ones, has expanded the mutational spectrum of OCA and enabled genetic counseling and prenatal diagnosis for the families.

Prevalence of antibiotic resistance and virulent factors in nosocomial clinical isolates of Pseudomonas aeruginosa from Panamá

ABSTRACT Background: Pseudomonas aeruginosa is an important causative agent of nosocomial infections. As pathogen, P. aeruginosa is of increasing clinical importance due to its ability to develop high-level multidrug resistance (MDR). Methods: The aim of the present study was to better understand the intrinsic virulence of circulating strains of Pseudomonas aeruginosa, by surveying and characterizing the antibiotic resistance profiles and prevalence of virulence factors in 51 clinical isolates of P. aeruginosa obtained from children admitted to Hospital del Niño-Panamá during the period of October 2016 until March 2017. Antimicrobial susceptibilities were assessed by determining the minimum inhibitory concentration for 12 antibiotics against P. aeruginosa clinical isolates using the VITEK system (https://www.biomerieux.com). Additionally, all isolates were examined by Polymerase Chain Reaction (PCR) for the presence of components of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes and betalactamases resistance genes (ESBL) using gene-specific primers. Results: A total of 51 pyoverdine producing clinical isolates were analyzed, all of which expressed resistance genes such as genes of the MexAB-OprM efflux pump system (mexABR) and pyoverdine receptor genes (fpvA). Out of 51 MDR isolates, 22 were ESBL producers. The most common ESBL gene was blaTEM expressed by 43% of the isolates. The isolates tested in this study showed increased resistance to antibiotics in the following categories: (i) penicillins (ampicillin (69%), piperacillin (22%); (ii) pyrimethamines (trimethoprim, 65%); (iii) nitrofurans (nitrofurantoin, 63%), and (iv) third-generation cephalosporin cefotaxime (53%). These results underscore a high prevalence of MDR amongst clinical isolates from Panama. Conclusions: The present study indicates that prevalence of BlaTEM-carrying strains is increasing with subsequent multidrug resistance in Panamá and as well reported worldwide. The virulent factors identified in this study provide valuable information regarding the prevalence of resistance genes and their potential impact on treatments that exploit the unique physiology of the pathogen. To prevent further spread of MDR, the proportions of resistant strains of Pseudomonas aeruginosa should be constantly evaluated on healthcare institutions of Panamá. More importantly, this information can be used to better understand the evolution and dissemination of strains hoping to prevent the development of resistance in Pseudomonas aeruginosa. Future studies quantifying the expression of these virulent genes will emphasize on the acquisition of multidrug resistance.

Identification and expression analysis of NRT1 family genes in Rehmannia glutinosa / 中国中药杂志

NRT1 family proteins play an important roles for absorbing and transporting of nitrate in different plants. In order to identify the NRT1 family genes of Rehmannia glutinosa, this study used 11 NRT1 homologous proteins of Arabidopsis as probe sequences and aligned with the transcriptome data of R. glutinosa by using NCBI BLASTN software. Resulting there were 18 NRT1 proteins were identified in R. glutinosa. On basis of this, a series of the molecular characteristics of R. glutinosa NRT1 proteins including the conserved domains, the transmembrane structure, the subcellular location and phylogenetic features were in detail analyzed. At same time, it were systematically analyzed that the temporal and spatial expression patterns and characteristics of R. glutinosa NRT1 family genes in response to different stress factors. The results indicated that 18 R. glutinosa NRT1 family genes with the length of coding region from 1 260 bp to 1 806 bp, encoded proteins ranging from 419 to 601 amino acids, and all of they owned the domains of typical peptide transporter with 7 to 12 transmembrane domains. These R. glutinosa NRT1 family proteins mostly were found to locate on cellular plasma membrane, and belonged to the hydrophobic proteins. Furthermore, the evolutionary analysis found that the 18 R. glutinosa NRT1 protein family could be divided into two subfamilies, of which 14 NRT1 family genes might occur the positive selection, and 4 genes occur the passivation selection during the evolution process of R. glutinosa. In addition the expression analysis showed that 18 R. glutinosa NRT1 family genes have the distinct expression patterns in different tissues of R. glutinosa, and their expression levels were also obvious difference in response to various stress. These findings infield that 18 R. glutinosa NRT1 family proteins might have obviously different functional roles in nitrate transport of R. glutinosa. In conclusion, this study lays a solid theoretical foundation for clarifying the absorption and transport molecular mechanism of N element during R. glutinosa growth and development, and at same time for deeply studying the molecular function of R. glutinosa NRT1 proteins in absorption and transport of nitrate.

Progression on Multifunctional Nanoparticles Interfering with Cell Membrane Transporters-associated Drug Resistance / 中国医学科学院学报

Multi-drug resistance(MDR)refers to the loss of sensitivity of tumor cells to traditional chemotherapeutics agents under the mediation of various mechanisms,resulting in the reduction of chemotherapy efficacy.Current studies suggest that a variety of factors,including cell membrane transporter-mediated efflux of anti-tumor drugs,special microenvironment in tumor tissue,DNA self-repair and anti-apoptotic process,and epithelial-mesenchymal cell transformation,may contribute to the formation of MDR.Cell membrane transporter-mediated drug efflux refers to an increase in the amount of anti-tumor drug pumped out of the cell through the up-regulation of the ATP-binding cassette transporter on tumor cell membrane,which reduces the concentration of the drug in the cell,thus forming MDR.An effective method to inhibit the efflux pump caused by overexpression of membrane transporters plays an important role in overcoming MDR.As a promising drug delivery system,multifunctional nanoparticles have demonstrated many advantages in antitumor therapy.Meanwhile,nanoparticles with tailored design are capable of overcoming MDR when combined with a variety of strategies.This paper described in detail the studies relevant to the use of multifunctional nano-sized drug delivery system combined with different strategies,such as co-delivery of agents,external responsiveness or target modification for intervention with efflux pump in order to reverse MDR.This paper provides reference for the development of nano-sized drug delivery system and the formulation of reversal strategy in the future.

Steroidogenic acute regulatory protein-related lipid transfer 4 (StarD4) promotes breast cancer cell proliferation and its mechanism / 生物医学工程学杂志

Oncogene StarD4 had the function of promoting proliferation and metastasis of triple-negative breast cancer (TNBC), but its clinical value and molecular mechanism are unknown. This paper found that StarD4 was highly expressed in cancer tissues of TNBC patients, and higher expression level of StarD4 in TNBC patient resulted in poorer prognosis. Based on transcriptomics of MDA-MB-231 cell model, the results of bioinformatics analysis showed that down-regulated expression level of StarD4 led to overall downregulation of cholesterol-relative genes and significant enrichment of cancer mechanism and pathway. Further analysis and investigation verified that StarD4 might cross-promote the protein stability of receptor ITGA5 through the cholesterol pathway to enhance TNBC progression, which provides guidance for clinical application of TNBC diagnosis and treatment.

Analysis of genetic variation for a child affected with congenital insensitivity to pain with anhidrosis and albinism by whole genome sequencing / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic variation of a Chinese family affected with congenital insensitivity to pain with anhidrosis and albinism.@*METHODS@#Whole exome sequencing (WES) was carried out to screen potential variants within genomic DNA extracted from the proband and his parents. Whole genome sequencing (WGS) was applied when variants were not found completely. Suspected variants were validated by Sanger sequencing.@*RESULTS@#WES has identified a heterozygous c.1729G>C (p.G577R) variant of NTRK1 gene and two heterozygous variants of OCA2 gene, namely c.1363A>G (p.R455G) and c.1182+1G>A. WGS has identified two additional heterozygous variants c.(851-798C>T; 851-794C>G) in deep intronic regions of the NTRK1 gene.@*CONCLUSION@#The compound heterozygous variants of the NTRK1 gene probably underlay the congenital insensitivity to pain with anhidrosis. And the compound heterozygous variants of the OCA2 gene probably underlay the albinism in the proband. In the case where no variant is detected by WES in the coding region, WGS should be considered to screen potential variants in the whole genome.

Research progress of correlation between multidrug resistance and transporters and traditional Chinese medicine intervention / 中国中药杂志

With the emergence of drug resistance in Western medicine, the repeated administration of clinical first-line drugs becomes more severe. There are many factors leading to multidrug resistance(MDR), so it is very difficult to solve the problem. Since traditional Chinese medicine(TCM) has been used in the field of MDR in recent years, the research on the transporter-associated drug resistance and intervention of TCM has gradually become a hot spot. Therefore, in order to further explore the relationships among drug resistance, transporters, and TCM intervention, we review the relevant research progress in recent years and comb the achievements and limitations of this research at present. In the end, we put forward the research direction of changing body's ADME through the host's transporters and gastrointestinal flora, which provides new ideas for future research.

Silicon Mediated Alleviation of Salinity Stress Regulated by Silicon Transporter Genes (Lsi1 and Lsi2) in Indica Rice

Abstract Silicon accumulation is known to improve tolerance of plants under both biotic and abiotic stress. Salinity stress is an inevitable crisis causing wide spread damage to rice leading to food insecurity. The influence of Si (1mM) on two rice cultivars cv. Ghanteswari (high accumulator) and cv.Badami (low accumulator) which differs in Si uptake potential under saline (10ds/m EC) and non- saline conditions were studied in nutrient culture. The Si transporter genes were isolated and characterized to determine their function in salinity tolerance. Under stress, there was an increase in Si accumulation, Na+/K+ ratio, electrolyte leakage, lipid peroxidation and antioxidant activities. On addition of silicon, the K+ uptake increased, membrane damage reduced and osmolytes balance improve under salinity. But, the level of resurgence was varied in both cultivars, due to their differential Si-accumulation. Molecular characterizations of Lsi1 protein revealed its involvement in the movement of ion and water and therefore prevent osmotic stress. The Lsi2 is responsible for removal of Na+, reducing salt toxicity. Silicon accumulation is responsible for maintenance of cell water status, osmotic balance and Na+ ion exclusion during high salinity. The variable relative expression of Lsi2 provides a possible explanation for differential genotypic uptake of silicon.

Analysis of P gene variations among fourteen patients with oculocutaneous albinism type II / 中华医学遗传学杂志

OBJECTIVE@#To analyze variations of TYR and P genes among 14 patients with clinically diagnosed oculocutaneous albinism.@*METHODS@#Potential variations of the TYR and P genes were detected by Sanger sequencing. Novel variations were predicted with bioinformatics software including SIFT and PolyPhen-2.@*RESULTS@#No variation was found in the TYR gene, while 9 types of variations were found in the P gene among the 14 patients, which included c.803-3C>G (7/26), c.1327G>A (p.Val443Ile) (5/26), c.632C>T (p.Pro211Leu) (4/26), c.1832T>C (p.Leu611Pro) (3/26), c.1349C>A (p.Thr450Lys) (2/26), c.2363C>T (p.Ser788Leu) (2/26), c.2228C>T (p.Pro743Leu) (1/26), c.1525A>G (p.Thr509Ala) (1/26), and c.1349C>T (p.Thr450Met) (1/26). Only 1 heterozygous variation was detected in 2 families. c.2363C>T (p.Ser788Leu), c.1832T>C (p.Leu611Pro) and c.1525A>G (p.Thr509Ala) were not reported previously and predicted as "harmful" to the protein function.@*CONCLUSION@#The main type of ocular albinism is oculocutaneous albinism type II in Liuzhou region, where the most common variations of the P gene were c.803-3C>G and c.1327G>A (p.Val443Ile). Above finding has enriched the variation spectrum of the P gene.

Paroxysmal crying and motor regression for more than two months in an infant / 中国当代儿科杂志

The patient was a male who was found to be abnormal at the age of 4.5 months. He presented with irritability, motor regression and opisthotonus. Brain MRI revealed bilateral abnormality in the lentiform nucleus, thalamus, deutocerebrum and cerebellar hemispheres. Novel compound heterozygous mutations of SLC19A3 gene, c.950G>A(p.G317E) and c.962C>T(p.A321V), were found in the patient. Further study showed that c.950G>A was inherited from his father and c.962C>T came from his mother. Using bioinformatics software analysis, both of the mutations were found to be harmful. His symptoms were improved remarkably after biotin, thiamine and "cocktail" therapy. One month later a brain MRI revealed that the lesions in basal ganglia and cerebellar hemispheres were improved. The patient was definitely diagnosed with biotin-thiamine responsive basal ganglia disease (BTBGD). BTBGD is a treatable autosomal recessive disease and early administration of biotin and thiamine may lead to clinical improvement.

Application of next generation sequencing for the diagnosis of congenital hearing loss / 中华医学遗传学杂志

OBJECTIVE@#To identify genetic mutations among patients with hearing loss but without common GJB2, SLC26A4, 12 SrRNA mutations.@*METHODS@#Thirty-three patients were subjected to next-generation sequencing (NGS). Suspected mutations were verified by Sanger sequencing.@*RESULTS@#Four patients were found to harbor previously known pathogenic variations, and four were found to carry suspicious pathogenic variations, which yielded a detection rate of 24.2%.@*CONCLUSION@#NGS can improve the detection rate for mutations underlying congenital hearing loss and improve the efficiency and accuracy of the diagnosis.

Deletional variant of REEP1 gene in a pedigree affected with spastic paraplegia type 31 / 中华医学遗传学杂志

OBJECTIVE@#To detect pathogenic variation in a pedigree affected with hereditary spastic paraplegia type 31 and explore its molecular pathogenesis.@*METHODS@#Customized Roche NimbleGen capture probes were used to capture all exons of the target genes in relation with hereditary spastic paraplegia. The DNA samples were also assayed with fluorescent quantitative PCR as well as chromosomal microarray analysis using CytoScan HD chip.@*RESULTS@#The proband and her father and grandfather were found to carry a deletion for position 85 992 693-86 842 693 on chromosome 2, which spanned approximately 900 kb and encompassed the REEP1 gene. The latter has been specifically associated with hereditary spastic paraplegia type 31. The same deletion was not found in her mother who is phenotypically normal.@*CONCLUSION@#The deletional variation of the REEP1 gene probably underlies the disease in this pedigree.

Modulation of drug-metabolizing enzymes and transporters under hypoxia environment / 生理学报

Drug metabolism is significantly affected under hypoxia environment with changes of pharmacokinetics, expression and function of drug-metabolizing enzymes and transporters. Studies have shown that hypoxia increases the release of a series of inflammatory cytokines which can modulate drug metabolism. Besides, both hypoxia inducible factor 1α (HIF-1α) and microRNA-mediated pathways play a role in regulating drug metabolism. This article reviewed the impact and single-factor modulating mechanisms of drug metabolism under hypoxia, and put forward the speculation and prospects of multi-factor modulating mechanisms.

Mutation analysis of two pedigrees with suspected oculocutaneous albinism / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical presentation and gene of 2 pedigrees with suspected oculocutaneous albinism(OCA), and provide basis for clinical classification, genetic counseling and prenatal diagnosis.@*METHODS@#Variants were identified using next-generation sequencing(NGS) and confirmed by Sanger sequencing in 2 pedigrees with suspected OCA. The pathogenicity of the variants was analyzed according to the American College of Medical Genetics and Genomics (ACMG) standard.@*RESULTS@#Two compound heterozygous mutations of TYR and OCA2 genes were identified respectively in 2 pedigrees with suspected OCA. The mutation of c.819+3insATATGCC in TYR and the mutation of c.1870G>C in OCA2 are first reported in this study. The pathogenicity analysis shows that two novel mutations are likely pathogenic by combination of prediction of SIFT, Polyphen-2 and Human Splicing Finder.@*CONCLUSION@#The findings of this study expand the mutational spectrum of OCA. Compound heterozygous mutations in the TYR and OCA2 gene may be responsible for clinical manifestations of 2 pedigrees with suspected OCA.

Renal physiology of urea transporters / 生理学报

Urea transporters (UTs) are transmembrane urea-selective channel proteins that include two UT subfamilies, UT-A and UT-B. UT-A subfamily includes six members, UT-A1 to UT-A6, which are mainly expressed in kidney. UT-B subfamily has only one member that has a wide distribution in the body. UTs have been confirmed to play important roles in urinary concentration via the phenotypic analysis of 6 UT selective knockout mouse models. Experimental results suggest that UTs might be diuretic targets and that UT inhibitors might be developed as novel diuretics. This article reviews the physiological function and drug discovery of UT.

Síndrome de anemia megaloblástica sensible a la tiamina de aparición en la niñez, con mutación en el genSLC19A2: caso clínico / Infantile-onset thiamine responsive megaloblastic anemia syndrome with SLC19A2 mutation: a case report

Antecedentes. El síndrome de anemia megaloblástica sensible a la tiamina (TRMA, por sus siglas en inglés), también conocido como síndrome de Rogers, se caracteriza por presentar anemia megaloblástica, hipoacusia neurosensorial y diabetes mellitus. Las alteraciones en el transporte de la tiamina hacia las células se deben a mutaciones homocigotas o heterocigotas compuestas en el gen SLC19A2. Presentación de un caso. Presentamos el caso de una niña que manifestaba sordera neurosensorial tratada con una prótesis auditiva, diabetes con necesidad de insulina y anemia macrocítica, tratada con tiamina (100 mg/día). El nivel de hemoglobina mejoró hasta alcanzar 12,1 g/dl después de aumentar la dosis terapéutica de tiamina hasta 200 mg/día. Conclusión. Se debe evaluar a los pacientes con TRMA para detectar anemia megaloblástica, hipoacusia neurosensorial y diabetes mellitus. Se les debe dar seguimiento para determinar la respuesta de la enfermedad hematológica y de la diabetes después de la terapia con tiamina. La dosis terapéutica de tiamina puede aumentarse según la respuesta clínica. Debe proporcionarse asesoramiento genético.

Background. Thiamine-responsive megaloblastic anemia syndrome (TRMA), also known as Rogers syndrome, is characterized by megaloblastic anemia, sensorineural hearing loss, and diabetes mellitus. Disturbances of the thiamine transport into the cells results from homozygous or compound heterozygous mutations in the SLC19A2 gene. Case presentation. We report a girl which presented with sensorineural deafness treated with a hearing prosthesis, insulin requiring diabetes, macrocytic anemia, treated with thiamine (100 mg/day). Hemoglobin level improved to 12.1 g/dl after dose of thiamine therapy increased up to 200 mg/day. Conclusion. Patients with TRMA must be evaluated for megaloblastic anemia, sensorineural hearing loss, and diabetes mellitus. They must be followed for response of hematologic and diabetic after thiamine therapy. It should be kept in mind that dose of thiamine therapy may be increased according to the clinical response. Genetic counseling should be given.