Journal of Genetics最新文献

The complete mitogenome of the common Chinese whip scorpion, Typopeltis sinensis (Butler, 1872) was sequenced and compared with another Uropygid mitogenome of Mastigoproctus giganteus (Lucas, 1835). Structural divergences include the absence of one tRNA-Leu and strand inversions in four protein coding genes (PCGs). All PCGs showed K_a/K_s ratios-1, which indicates purifying selection, with COI (0.04) evolving the most conservatively and ATP8 (0.65) accumulating the highest nonsynonymous substitutions. Phylogenetic reconstruction based on 602-bp COI sequences from seven species indicates that T. sinensis is most closely related to T. stimpsonii.

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.

High-altitude ecosystems in the Himalayas exhibit extreme seasonal variations in their vegetation, with summer and winter presenting the most pronounced environmental contrasts. As winter progresses, temperatures drop, and deciduous plant species undergo senescence. This study unravels the transcriptomic dynamics driving leaf senescence in Himalayan treeline species, Betula utilis, during seasonal variations. Using the RNA-sequence technology, leaf samples collected under fresh and senescent stages were analysed to deduce expression profiles at different stages. A total of 6505 differentially expressed transcripts were identified, with functional annotations revealing key senescence pathways such as phytohormonal regulation, chlorophyll degradation, and nutrient remobilisation. The upregulation of senescence-associated genes (SAGs), alongside alterations in transcription factors like WRKY and hormonal pathways, highlights the molecular interplay driving seasonal adaptation. Additionally, chlorophyll catabolism, modulated by NYC1 and PAO, was observed as a pivotal response to winter conditions. The findings of the study provide insights into the importance of carbohydrate metabolism, hormonal signalling, and stress adaptation-related pathways in nutrient conservation and plant fitness under environmental stress. This study offers a comprehensive understanding of the genetic mechanisms that allow B. utilis to withstand the harsh Himalayan climate, adding invaluable information to the fields of plant senescence, stress physiology, and climate resilience.

Ageing involves deterioration in physiological processes, such as maintenance of neuronal health, muscle, fat bodies, and gut bacteria, which play a crucial role in the progression of ageing. In this study, we show that the expression of Taxi, a transcription factor is required to maintain the lifespan in Drosophila melanogaster. Hypermorphic and hypomorphic alleles of taxi show reduced lifespan. We have identified that pan-neuronal overexpression and knockdown of Taxi lead to a stark reduction in the lifespan. In our previous study, we showed that Taxi negatively regulates Adar. Interestingly, overexpression of Adar significantly rescued the reduction in lifespan caused by taxi overexpression in neurons. Conversely, the knockdown of Adar rescued the defective lifespan caused by taxi knockdown in neurons. We show that enzymatically inactive Adar also rescued the reduced lifespan in flies having a neuronal taxi overexpression background. Our work suggests that, besides the editing activity, Adar may have editing-independent roles implicated in lifespan regulation. Overall, we show that neuronal tissue-specific controlled expression of taxi and its interacting partner Adar is imperative in lifespan maintenance.

The Chhattisgarh duck (Anas platyrhynchos L., 1758) is a native Indian germplasm that provides crucial support for the local food security and livelihoods in the eastern region of India. For sustainable use, preservation and conservation, it is crucial to understand its genetic identity and relationships with other breeds of duck. This study focuses on the identification of mitochondrial genome sequence of Chhattisgarh duck. The complete genome of the Chhattisgarh duck is 16,604-bp long, with 37 genes arranged in the same order and on the same strands as those in other species and breeds of Anas. Phylogenetic analysis shows that the Chhattisgarh duck is the sister to a group comprising multiple Mallard breeds and the Maithili breed as sister group, within a structure (((('Mallard' + Maithili) + Chhattisgarh) + Bengal) + Bihar), in which Bihar is the sister to all other known breeds of A. platyrhynchos. The germplasm of Maithili, Chhattisgarh, Bengal, and Bihar ducks are phenotypically as well as phylogenetically distinctive. This study shows the importance of identification and conservation of native Indian duck germplasm.

Schimke immunoosseous dysplasia (SIOD) is an uncommon inherited genetic disorder resulting from pathogenic variants in the SMARCAL1 gene. This complex condition exhibits a wide range of clinical features, including skeletal abnormalities, steroid-resistant nephrotic syndrome, and immune system deficiencies. In this study, we report a case series of three patients diagnosed with SIOD, each harbouring copy number variants in the SMARCAL1 gene. The cases expand the current understanding of the genetic diversity underlying SIOD and highlight the significance of copy number variations as a pathogenic mechanism. Our findings contribute to broadening the genotypic spectrum associated with SIOD and underscore the importance of comprehensive genetic analysis for accurate diagnosis and management of this rare disorder.

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.

The nonexpressor of pathogenesis-related 1 (NPR1) is the salicylic acid (SA) receptor, which plays an important regulatory role in plant immunity. However, the NPR1-like gene family in maize has not been comprehensively identified and analysed. In the present study, we identified gene structures, conserved motifs, cis-elements, and expression patterns in different tissues and organs, and under biotic and abiotic stresses. The NPR1-like proteins of different species are highly conserved during evolution. Many cis-acting elements have been identified in the promoter region of NPR1-like genes in maize, including elements that respond to growth and development, biotic and abiotic stresses, and plant hormones. Furthermore, the transcript abundance of all NPR1-like genes in maize changed significantly under abiotic treatments (cold, heat, salt, or drought treatments), phytohormone treatments and pathogen treatment (Ustilago maydis), indicating that they might be involved in biotic and abiotic stresses. In addition, ZmNPR1 is located in the cytoplasm, and overexpression of ZmNPR1 improves the resistance of maize plants to U. maydis. The findings of the present study might provide important information on under standing the complexity of the NPR1-like genes and their functions in maize.