Journal of Genetics最新文献

This study aimed to understand the maternal influence on the inheritance of pericarp colour and grain dimensions in rice, serving as a model for maternal effects in plants. Four crosses, namely Kalarata (red pericarp) x DRR Dhan 58 (white pericarp), DRR Dhan 58 x Kalarata, Kalarata x Pusa 44 (white pericarp), and Pusa 44 x Kalarata, were attempted and their F₁, F₂ and F₃ seeds were analysed. All F₁ seeds of all crosses exhibited the pericarp colour of their corresponding maternal parent, confirming a strong maternal influence. In subsequent generations, F₂ seeds uniformly exhibited red pericarp colour across all crosses, thus reinforcing the influence of maternal genotype on inheritance. However, F₃ seeds were segregated into 9 red: 3 medium red: 4 white, suggesting digenic recessive epistasis (supplementary gene action). Phenotypic assessments indicated nuclear inheritance with maternal effects, while genotypic analysis using gene-based markers revealed polymorphisms at 'Rc' locus and monomorphism at 'Rd' locus, indicating the presence of specific genetic factors in the parental materials used in the study. Additionally, analysis of the grain L/B ratio revealed a similar trend to pericarp colour inheritance, with direct maternal genetic effects in F₁ seeds, consistent uniformity in F₂ seeds and continuous variation in F₃ seeds across all crosses. Welch's test comparisons of L/B ratios suggested a significant maternal impact, particularly in F₃ and F₂ generations, with paternal influence remaining consistent across generations. Deviations in the L/B ratios in certain F₃ segregants suggest environmental influences on grain development. These findings contribute to the understanding of maternal effects in plants and have important implications for rice breeding. The significance of this research lies in its contribution to the relatively unexplored field of maternal effects in plant genetics.

The sev-Gal4 driver is widely used in Drosophila to express the target gene in specific subsets of cells in ommatidial units of the developing eye. A 2015 report (Ray and Lakhotia, J. Genet. 94, 407-416) from our laboratory claimed that besides the eye disc cells, the sev-Gal4 (Bloomington stock 5793) also expresses in eight pairs of dorsomedial neurons and some other cells in larval and early pupal ventral ganglia. The current study reveals that this claim was incorrect since the UAS-GFP transgene in Bloomington stock 1521 used as a reporter in the 2015 study expresses in the eight pairs of dorsomedial neurons and some other cells in larval and early pupal ventral ganglia even in undriven condition. The UAS-eGFP reporter in the BL-5431 stock, however, does not express in these ganglia, neither in undriven nor in sev-Gal4 driven condition. This was also confirmed by the G-TRACE cell lineage study. Present results suggest that only four dorsalmidline cells in the ventral ganglia and a cluster of cells in the central region of the brain hemisphere, besides the earlier known cells in the eye disc and optic lobe of the brain, express the sev-Gal4 transgene in the stock 5793. The essentiality of examining the undriven expression of a transgene cannot be over-emphasized.

Cetuximab has been indicated as the mainstay of metastatic colorectal cancer (CRC) therapy, of which application was impeded by chemoresistance that was casually attributed to KRAS mutation. This study sought to determine whether YY1 mediated the resistance of CRC cells harbouring KRAS mutation (KRASmut) to cetuximab. The expression of YY1 between cetuximab response and resistance was investigated in cancerous tissues from CRC patients received cetuximab therapy comprising eight KRAS wild-type (KRASwt) and 12 KRASmut. The relationship between YY1 expression and cetuximab resistance was explored based on KRASmut and KRASwt CRC cell lines. To explore the role of YY1 in the cetuximab resistance of KRASmut CRC cells, the response to cetuximab was investigated in cetuximab-resistant cells (SW620-R) with YY1 silence and cetuximab sensitive cells (HCT116) with YY1 overexpression. EGFR/Akt/ERK signalling activation, as well as mRNA and active GTP-bound KRAS level were assessed after the treatment. In KRASmut CRC tissues, YY1 expression was correlated with the histological grade and the cetuximab resistance. Significantly markable differences in YY1 expression between cetuximab-resistant and the parental cell lines were found in KRASmut cells. Silencing YY1 resensitized SW620-R cells to cetuximab and led to an elevation of the active GTP-binding KRAS. Conversely, the capability against cetuximab and GTP-binding KRAS activation of HCT116 cells was enhanced by overexpressing YY1. The blockage of EGFR/Akt/ERK signalling by cetuximab was re-observed in SW620-R cells after silencing YY1 but impaired in HCT116 by overexpressing YY1. The YY1 mediates the resistance of KRASmut CRC cells to cetuximab.

Duchenne muscular dystrophy (DMD) is a severe genetic disorder characterized by progressive muscle degeneration and loss of function due to the absence of dystrophin. In this study, we utilized a zebrafish model with a dmd gene knockout to explore the therapeutic potential of JAG1 overexpression in mitigating DMD-associated muscle dysfunction. Dystrophic zebrafish larvae displayed significant impairments in muscle function, evidenced by reduced swimming abilities, decreased birefringence, and disrupted β-dystroglycan localization, indicative of structural degeneration. Overexpression of JAG1, achieved via plasmid injection, partially restored muscle function, as reflected by improvements in stride length and total swimming distance. However, the structural integrity of slow oxidative muscle fibers remained largely unaffected, with a functional decline from 4 to 8 days post-fertilization (dpf) being more indicative of disease progression than structural changes. These findings suggest that the rescue effect of JAG1 overexpression may not be due to the preservation of slow oxidative fibers but rather through a mechanism that reduces susceptibility to contraction-induced injury. Notably, our study faced limitations related to the control of JAG1 expression levels and tissue specificity. Our results highlight the complexity of DMD pathology, where muscle structure and function do not always correlate, emphasizing the need for refined functional assays to better assess therapeutic outcomes. By incorporating functional recovery assessments at 8-10 dpf, zebrafish models can serve as more predictive preclinical tools, potentially enhancing the translational relevance of findings and reducing risks for patients in clinical trials. This study investigates how increasing the levels of a protein called JAG1 can help improve muscle function in a zebrafish model of DMD. By showing partial recovery of muscle activity, the findings suggest new therapeutic strategies that could potentially slow disease progression and improve patient outcomes.

Raising Iraqi indigenous chickens (IIC) is restricted by their thin and low eggshell weights. Due to the importance of the prolactin (Prl) gene in regulating a wide range of egg production traits, this study assessed the potential genetic polymorphisms associated with Prl that may influence these traits. The polymorphism was examined in three Prl loci of the IIC breed (n = 120) in comparison with the standard Hyline breed (n = 120). The polymorphism of both breeds was associated with eggshell weight and thickness indices for 16 weeks, starting from the 44th to the 59th week. After genotyping three loci within Prl by polymerase chain reaction-single-stranded conformation polymorphism (SSCP) method, only one novel SNP was identified in intron 4, namely 129G > A. The identified intron SNP exerted a significant association with both eggshell thickness and weight indices throughout the investigation period. Birds with GG genotype exhibited higher indices of eggshell thickness and weight than those with the GA and AA genotypes, respectively. The employed in silico tools predicted a remarkable ability for the identified SNP to alter the mRNA splicing pattern, which might be related to altered prolactin activity in birds having an alternative allele A. This study is the first to suggest the significance of this novel intron SNP in assessing eggshell traits in chickens.

Vitamin-D deficiency (VDD) is a global health concern. It is known to play a critical role in the immunomodulation, and thus, its metabolism could be investigated to unravel its contribution in common immune-mediated diseases, e.g., celiac disease (CD). Genotyping of SNPs from vitamin D receptor (VDR) gene, such as rs11568820 (Cdx2) and rs2228570 (Fok1) using allele specific multiplex polymerase chain reaction (ASM-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) respectively; and rs7041 and rs4588 of vitamin D binding protein (VDBP/GC) using PCR-RFLP were done in 969 subjects including CD cases (n=506) and controls (n=463). Genotype data for 86 CD and 712 controls for rs11568820 and rs7041 were retrieved from already published Immunochip genotype data. Serum concentration of vitamin-D and vitamin D binding protein (VDBP) were measured for 283 participants (98 CD and 185 controls). rs4588-A allele was identified as protective allele [OR=0.6(0.4–0.7), P<0.0001]. Significantly reduced serum level of vitamin-D was observed in CD patients [median=16.25 ng/mL, IQR (8.94–23.60)] than in controls [median=19.94 ng/mL, IQR (13.91–28.46)] with P=0.001. Notably, rs7041-GG, rs4588-CC, and 1F (GC) haplotype of VDBP/GC showed significant association (P<0.05) with reduced serum vitamin D level. We did not find any significant association with VDBP serum concentration. Significant vitamin D and VDBP level correlations were observed in controls (spearman r = 0.3, P=0.005). The present study highlights the significance of reduced vitamin-D serum level in CD. 1F variant of VDBP and lower vitamin-D levels contribute to CD. No correlation between vitamin-D and VDBP levels suggests that vitamin-D supplementation may improve vitamin-D levels but might not affect VDBP levels in CD subjects.

The most severe type of male infertility is nonobstructive azoospermia (NOA), where there is no sperm in the ejaculate due to failure of spermatogenesis. The predictable frequency of NOA in the general population is one in 100 men. Genetic studies have recognized dozens of NOA genes. Most NOA aetiologies remain idiopathic. Monogenic mutations can be a reason for a part of idiopathic NOA cases. To address this, we studied the pedigree of a consanguineous family with three NOAs by a family-based exome sequencing. Our goal was to pinpoint the genetic variants responsible for idiopathic NOA to aid future clinical genetic diagnostics and treatment strategies. Bioinformatics analysis followed by Sanger sequencing revealed that NOA patients were homozygous for a rare novel missense variant in PNLDC1 (NM_173516:exon9:c.710G>A;p.Gly237Asp). In silico, single-cell RNA sequencing data analysis and protein modelling demonstrated that PNLDC1, Gly237Asp resided in the conserved region of the CAF1 domain which could lead to local instability in the structure and alteration of protein phosphorylation site. We conclude that the novel missense PNLDC1 variant may affect meiosis and spermatogenesis, leading to NOA and the genetic cause of this idiopathic NOA family. Our result helps genetic counselling for idiopathic NOA cases and provides the occasion for more efficient diagnosis in the clinical setting.

Upregulation of homeoprotein SIX1 in gastric cancer (GC) is related to tumour proliferation and invasion. MicroRNA-7160 (miR-7160) is a homeoprotein SIX1-targeting miRNA that downregulates miR-7160, leading to cancer development. Total gastric cancer samples were collected from six patients, and relative expression levels of SIX1 mRNA and miRNAs were analysed by qRT-PCR. To evaluate the regulation of SIX1 by miR-7160, pGL3-SIX1-mut, pGL3-SIX1, and miR-7160 mimics transfected into cells using lipofectamine 2000. After transfection, proliferation and apoptosis in cultured cells were assessed using the nuclear TUNEL staining and CCK8 reagent, respectively. We demonstrated that the downregulation of miR-7160 in human gastric cancer cells is related to the upregulation of SIX1 mRNA. In gastric cancer cell lines, miR-7160 overexpression could downregulate the expression and inhibit cancer cell proliferation and growth in vitro. However, overexpression of miR-7160 did not increase gastric cancer cell apoptosis. In vitro downregulation of SIX1 decreased vimentin, N-cadherin, and other EMT-related gene expression and increased E-cadherin expression. In brief, miR-7160, by targeting SIX1, inhibits gastric cancer proliferation and cell growth in vitro, which provides an idea for introducing a new treatment option for gastric cancer.

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+5G>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.