Journal of Genetics最新文献

MOCA1 encodes the last key glucuronosyltransferase for ionic stress sensor glycosyl inositol phosphoryl-ceramide (GIPCs) biosynthesis in Arabidopsis, which indicates that the MOCA gene family play important role in plant tolerance to salt stress. However, the isolation and function of MOCAs in staple crops have not been reported and the downstream targets of MOCAs in salt stress tolerance signalling pathway are not clear. In this study, we identified 110 MOCA genes in wheat which were classified into five clades and they differed in gene structure, protein length, conserved motifs and expression profiles in different tissues and under salt stress. TaMOCA1 was selected for further functional study in response to salt stress. TaMOCA1 was rapidly induced by NaCl treatment. The 35S::TaMOCA1-GFP construction showed the cell nucleus and cytoplasm location in wheat protoplast. TaMOCA1 over-expressing Arabidopsis seedlings formed longer primary roots and more lateral roots than the wild type ones under 50 mM NaCl treatment. The over-expressing Arabidopsis had higher expression levels of HKT1, but lower expression levels of NHX1 and SOS genes than the wild type. Also, the transgenic plants had higher SOD activity and lower MDA content than the wild Arabidopsis seedling under salt stress. These results may indicate that TaMOCA1 increases salt stress tolerance through decreasing Na⁺ loading from the xylem parenchyma cells to the xylem via SOS1 and HKT1, hence lowering root-to-shoot delivery of Na⁺ and superior antioxidant ability. All these results lay a foundation for further functional study of MOCAs in wheat.

Abstract

Saccharomyces cerevisiae has been demonstrated to be an excellent platform for the multi-fragment assembly of large DNA constructs through its powerful homologous recombination ability. These assemblies have invariably used the stable centromeric single copy vectors. However, many applications of these assembled genomes would benefit from assembly in a higher copy number vector for improved downstream extraction of intact genomes from the yeast. A review of the literature revealed that large multi-fragment assemblies did not appear to have been attempted in multicopy vectors. Therefore, we devised a toolkit that would enable one to seamlessly transition with the same assembling fragments between a single copy and a multicopy vector. We evaluated the assembly of a 28 kb attenuated SARS-CoV-2 genome (lacking the N gene) from 10 fragments in both single copy and multicopy vector systems. Our results reveal that assembly was comparably efficient in the two vector systems. The findings should add to the synthetic biology toolkit of S. cerevisiae and should enable researchers to utilize any of these vector systems depending on their downstream applications.

Abstract

Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases in women. In recent years, the effects of vitamin D receptor (VDR) gene variants and VitD3 levels on clinical features of PCOS have been frequently described. In this study, we aimed to determine the relationship between VDR ApaI, TaqI and Cdx2 gene variants and VitD3 levels in PCOS patients. Patients were divided into two groups: BMI<25 and BMI≥25. VDR genotypes were determined by real-time polymerase chain reaction (PCR) and serum VitD3 levels were examined by ELISA. We observed that frequencies of the Apa1 AC genotype, C allele and Cdx2 T allele are increased in the BMI≥25 group compared to BMI<25 group. Also, the ApaI C allele, Taq1 AA genotype and A allele, Cdx2 CC genotype and C allele are associated with increased triglyceride, total cholesterol, LDL-cholesterol levels in patients with BMI≥25. When examining the relationship between VitD3 levels and clinical profiles in all PCOS patients, regardless of BMI distinction, it is determined that there is a positive correlation between LDL-cholesterol and ftestosterone levels. The present findings suggest that VDR variants are one of the most important risk factors for PCOS, especially for patients with BMI≥25.

Dissecting the molecular basis of adaptation remains elusive despite our ability to sequence genomes and transcriptomes. At present, most genomic research on selection focusses on signatures of selective sweeps in patterns of heterozygosity. Other research has studied changes in patterns of gene expression in evolving populations but has not usually identified the genetic changes causing these shifts in expression. Here we attempt to go beyond these approaches by using machine learning tools to explore interactions between the genome, transcriptome, and life-history phenotypes in two groups of 10 experimentally evolved Drosophila populations subjected to selection for opposing life history patterns. Our findings indicate that genomic and transcriptomic data have comparable power for predicting phenotypic characters. Looking at the relationships between the genome and the transcriptome, we find that the expression of individual transcripts is influenced by many sites across the genome that are differentiated between the two types of populations. We find that single-nucleotide polymorphisms (SNPs), transposable elements, and indels are powerful predictors of gene expression. Collectively, our results suggest that the genomic architecture of adaptation is highly polygenic with extensive pleiotropy.

Abstract

This article aimed to detect the existence of barley-specific Nikita and Sukkula retrotransposons in domestic geese samples and to evaluate the evolutionary relationships between these and other transposons belonging to the family Anatidae. Inter-retrotransposon-amplified polymorphism-polymerase chain reaction (IRAP-PCR) method was performed for these retrotransposons movements in three diverse domestic goose populations (Chinese × Embden crossbred, Turkish White, and Turkish Multicolor). Polymorphism ratios were between 0 and 33% in all samples for Nikita and 0–73% in all samples for Sukkula. In addition, intrapopulation genetic polymorphism rates were also 0–15% in Chinese × Embden crossbred, 0–25% in Turkish White, 0–25% in Turkish Multicolor for Nikita; while 0–27% in Chinese × Embden, and 0–50% in Turkish Multicolor for Sukkula. There was no polymorphism for Sukkula among Turkish White samples. Moreover, the neighbour-joining method was used for phylogenetic tree construction using 38 sequences of different ducks, geese, and swans. In silico analyses supported the transitions of retrotransposons in the family Anatidae. It is concluded that transposon mobility among the phylogenetically distant species may lead to understanding evolutionary relationships. This report is one of the first studies investigating retrotransposon movements in domestic geese, revealing a new perspective on the goose genome regarding mobile genetic elements.

Absorptive hypercalciuria (AH) is a prevalent cause of kidney stones, and the adenylate cyclase 10 (ADCY10) gene is a rare causative gene of AH. This study aims to investigate the genotypic and phenotypic characteristics of patients with AH caused by ADCY10 gene mutations. Whole-exome sequencing and Sanger sequencing were performed on the probands and their family members, respectively. Clinical and genetic data of patients with AH caused by ADCY10 gene mutations were collected and analysed retrospectively from the present study and published literature. Two female patients (6 years old and 1 year old) with multiple bilateral kidney stones were found to have a heterozygous c.3304T>C mutation and a heterozygous c.1726C>T mutation in the ADCY10 gene. Urinary metabolite analysis revealed that urine calcium / creatinine ratios were 0.95 mmol/mmol and 1.61 mmol/mmol, respectively. Both patients underwent thiazide intake postoperatively, and upon reexamination, urine calcium decreased to within the normal range. A total of 61 patients with AH were reported from previous and present studies. The sex ratio was 7:5 for males to females, and the mean age of onset was 23.61±20.08 years. A total of 16 ADCY10 gene mutations were identified, including seven missense (43.75%), five splicing (31.25%), two frameshift (12.50%) and two nonsense mutations (12.50%). Only two cases were identified as homozygous mutations (c.1205_1206del), and the others were heterozygous mutations. In summary, we identified two novel ADCY10 gene candidate pathogenic variants in Chinese pediatric patients, which expands the mutational spectrum of the ADCY10 gene and provides a potential diagnostic and therapeutic target.

Abstract

Fixation index (F_st) statistics provide critical insights into evolutionary processes affecting the structure of genetic variation within and among populations. F_st statistics have been widely applied in population and evolutionary genetics to identify genomic regions targeted by selection pressures. The FSTest 1.3 software was developed to estimate four F_st statistics of Hudson, Weir and Cockerham, Nei, and Wright using high-throughput genotyping or sequencing data. Here, we introduced FSTest 1.3 and compared its performance with two widely used software VCFtools 0.1.16 and PLINK 2.0. Chromosome 1 of 1000 Genomes Phase III variant data belonging to South Asian (n = 211) and African (n = 274) populations were included as an example case in this study. Different F_st estimates were calculated for each single-nucleotide polymorphism (SNP) in a pairwise comparison of South Asian against African populations, and the results of FSTest 1.3 were confirmed by VCFtools 0.1.16 and PLINK 2.0. Two different sliding window approaches, one based on a fixed number of SNPs and another based on a fixed number of base pair (bp) were conducted using FSTest 1.3 and VCFtools 0.1.16. Our results showed that regions with low coverage genotypic data could lead to an overestimation of F_st in sliding window analysis using a fixed number of bp. FSTest 1.3 could mitigate this challenge by estimating the average of consecutive SNPs along the chromosome. FSTest 1.3 allows direct analysis of VCF files with a small amount of code and can calculate F_st estimates on a desktop computer for more than a million SNPs in a few minutes. FSTest 1.3 is freely available at https://github.com/similab/FSTest.

The genus Indotyphlops has a widespread distribution in the Indian landmass and Southeast Asia, with 20 reported species. The current classification within the genus is based on morphology. In this study, we sampled all the reported Indotyphlops species from subcontinental India, to resolve relationships within this genus and to understand biogeographic patterns that resulted in the widespread distribution. We generated sequences for five nuclear markers which were used in the global typhlopoid phylogeny and built phylogenetic trees of the superfamily Typhlopoidea. We also carried out divergence time analysis and biogeographic analysis to understand the time and modes of dispersal and diversification of these species. The results show Indotyphlops sensu lato to be polyphyletic, with the clade consisting of I. porrectus and I. exiguus sister to a clade consisting of the southeast Asian typhlopid genera Ramphotyphlops, Anilios, Malayotyphlops, Acutotyphlops, Sundatyphlops, and Indotyphlops sensu stricto. The other clade consists of I. pammeces and I. braminus from the Indian subcontinent and I. albiceps from Southeast Asia. Biogeographical analysis suggests two dispersals from Asia to the Indian landmass—an earlier dispersal from Eurasia into India led to the lineage consisting of I. porrectus and I. exiguus, followed by a later dispersal that evolved into I. pammeces and I. braminus. These results necessitate a taxonomic revision. We propose the genus Pseudoindotyphlops gen. nov. for the clade currently consisting of the most recent common ancestor (MRCA) of I. porrectus and I. exiguus, and all descendants thereof.

Absorptive hypercalciuria (AH) is a prevalent cause of kidney stones, and the adenylate cyclase 10 (ADCY10) gene is a rare causative gene of AH. This study aims to investigate the genotypic and phenotypic characteristics of patients with AH caused by ADCY10 gene mutations. Whole-exome sequencing and Sanger sequencing were performed on the probands and their family members, respectively. Clinical and genetic data of patients with AH caused by ADCY10 gene mutations were collected and analysed retrospectively from the present study and published literature. Two female patients (6 years old and 1 year old) with multiple bilateral kidney stones were found to have a heterozygous c.3304T>C mutation and a heterozygous c.1726C>T mutation in the ADCY10 gene. Urinary metabolite analysis revealed that urine calcium / creatinine ratios were 0.95 mmol/mmol and 1.61 mmol/mmol, respectively. Both patients underwent thiazide intake postoperatively, and upon reexamination, urine calcium decreased to within the normal range. A total of 61 patients with AH were reported from previous and present studies. The sex ratio was 7:5 for males to females, and the mean age of onset was 23.61±20.08 years. A total of 16 ADCY10 gene mutations were identified, including seven missense (43.75%), five splicing (31.25%), two frameshift (12.50%) and two nonsense mutations (12.50%). Only two cases were identified as homozygous mutations (c.1205_1206del), and the others were heterozygous mutations. In summary, we identified two novel ADCY10 gene candidate pathogenic variants in Chinese pediatric patients, which expands the mutational spectrum of the ADCY10 gene and provides a potential diagnostic and therapeutic target.

The COQ7 gene is one of the causative genes for primary COQ10 deficiency-related disorders. OMIM-related phenotypes include severe encephalo-myo-nephrocardiopathy and distal hereditary motor neuronopathy. In the present study, we performed the exome sequencing analysis on the proband of a single family with two siblings affected by hereditary spastic paraparesis (HSP). Segregation analysis was conducted on the affected siblings and parents using the Sanger sequencing. In silico secondary and tertiary pre-mRNA structure analysis and protein modelling were carried out. Exome sequencing identified a homozygous splice site variant in the COQ7 gene (NM_016138.5: c.367+G>A) in the proband. Sanger sequencing confirmed the homozygous status in the affected sibling and heterozygous status in both parents, consistent with autosomal recessive inheritance. In silico secondary and tertiary premRNA structure analysis and protein modelling predicted the deleterious nature of the variant. This case highlights a distinct intermediate phenotype of COQ7 related disorders comprising early-onset spastic paraparesis due to a novel splice site variant in the COQ7 gene. This expands the spectrum of clinical manifestations associated with COQ7 deficiency and underscores the importance of considering COQ7 gene mutations in the differential diagnosis of HSP.