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The inheritance of the mitochondria genome and its diversity is unique for genetic and evolutionary studies relative to nuclear genomes. Northeast India and Himalayan regions are considered as one of the centres of indica rice origin. Also, rice diversity in northeast India is very distinct and highly suited for evolutionary studies. Although reports are available on the genetic diversity of indigenous northeast rice landraces, its relationship with the wild relatives is not yet properly explored and understood. In an attempt, mitochondrial markers were used to study the evolutionary relationship between the 68 landraces of northeast India and wild relatives ( O. rufipogon and O. nivara ) along with IR64 ( indica ) and Nipponbare ( japonica ) were taken as reference cultivars. Phylogenetically, the findings include two distinct clusters in the indigenous northeast India landraces representing indica and japonica groups. Further, the wild relatives and ~60% of northeast India landraces were identified to be closely related to the Nipponbare cluster. Besides, landraces of northeast India grouping with the indica group (IR64) are characterized by the absence of wild relatives. This indicates that there are two distinct evolutionary paths in the origin of northeast Indian rice landraces based on mitochondrial markers diversity and it is proposed that the inheritance of mitochondria, mitonuclear genome interactions, and bottleneck events could have genetically separated these two phylogenetically unique groups of northeast rice landraces.

Yellow mosaic disease (YMD) of pulses caused by mungbean yellow mosaic virus is a major threat to crop production. An infection that is compatible with regulating and interacting host proteins and the virus causes YMD. Oberon families of proteins OBE1-4 and VIN1-4 are imperative for plants, functions in meristem and vascular development, and were also regulated during compatible disease infection. Furthermore, in-silico expression results suggested the involvement of OBE1 and OBE2 proteins during virus infection of Vigna, Arabidopsis and soybean. Moreover, a common ancestor for the meristem and virus movement related Oberons was inferred through phylogenetic analysis. Protein interaction studies showed three amino acids (Aspartate, glutamate and lysine) in the plant homeodomain (PHD), involved in interaction with the N-terminal region of the virus movement protein and were also conserved in both monocot and dicots. Additionally, major differences in the nuclear localization signal (NLS) showing clade specific conservation and significant variation between dicots and monocots were ascertained in meristem and virus movement related Oberons. Consequently, a combination of PHD, CCD and their interactions with the VPg viral domain increases the susceptibility to YMD. Further, modification in the NLS regions of the viral movement clade Oberons, to knock out allele generation in the OBE1 and OBE2 homologs through genome-editing approaches could be established as alternate strategies for the improvement of host resistance and control yellow mosaic disease in plants, especially in pulse crops., (© 2022. The Author(s) under exclusive licence to The Botanical Society of Japan.)

Background: The potential of paddy breeding has reached its pinnacle, and hybrids have been the principal research outcome. Hence, our hypothesis was based on improvising the callus induction efficiency of recalcitrant Oryza sativa sub. indica hybrids by intervening into their cellular functions like cell division and histone regulation for the production of doubled haploids, a better output compared to hybrids., Methodology and Results: Insight into the mechanism of cell division is the foremost concern in altering the same and hence studies on evolution, expression and action of histone deacetylase and its 12 genes (9 HDA and 3 HD-tunin genes) were chosen in the hypothesis. Expression of HDA genes at three stages (anther dehiscence, 1st callusing and second callusing stages) with inhibitor (trichostatin-A) interventions indicated 1st callusing stage as the most important in influencing callus induction and also the genes HDA19, 6, 15 and 5 were the most important. TSA alone had a significant impact on the regulation of the genes HDT 702, HDA19, HDA9, and HDA6. Higher expression of HDA19 and HDA6 was involved in maximizing callus induction; HDA15 had an antagonistic expression compared to HDA19/6 and might be involved in chlorophyll regulation during regeneration. Results of evolutionary analysis on histone deacetylases indicated a long and single lineage of origin denoting its importance in the basic cellular functions. The tubulin deacetylation gene HDA5, which was exclusively found in dicotyledons, had a recent evolutionary history only from terrestrial plants, and also had significant conservation in its motifs and NLS region., Conclusion: By combating the recalcitrant nature of Indica cultivars, molecular editing on a combination of HDA genes will enhance the callus induction and regeneration efficiency of the next generation of doubled haploids, therby improving the total yield., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Diarrheagenic Escherichia coli O157 is an important reason for largest food borne inflectional outbreaks. E. coli O157 invades into the food chain through contaminated irrigation water and soil causing infectious diseases to humans. In our previous study, we have evaluated the persistence of E. coli O157 through plate count methods. However, conventional cultural procedures are less sensitive to discriminate the pathogenic strain and are time consuming. Therefore, in the present study we have enumerated the persistence of E. coli O157 in soil and vegetables using specific shiga toxin genes (stx1, stx2) through quantitative PCR. Initially, we have standardized a simple Sephadex-based DNA extraction protocol that could detect 2-3 cells/25g of vegetables. Further, quantitative PCR analysis showed a 10 3 fold difference in the enumeration of persistence as compared to simple plating techniques. Thus, qPCR-based persistence study can be used for rapid and accurate detection techniques for analyzing E. coli O157 contamination. PRACTICAL APPLICATIONS: Our experiment on E. coli O157 expression could be used as a scale for further studies on E. coli O157 pollution in the cropped soils, additionally the DNA extraction protocol experimented by us could be used in all sensitive quantitative assays, as it could detect the expression in lowest cell loads. However, our methodology is a more reliable and sensitive assay compared to normal cultural methods. Our experiment provides a strong evidence of persistence of E. coli O157 prevailing up to half or full cropping season., (© 2019 Wiley Periodicals, Inc.)

Long-term mechanical circulatory support devices, especially left ventricular assist devices, are being increasingly utilized in the management of end-stage heart failure either as bridge to heart transplantation, recovery or as destination therapy. However, current technology for controllers and alarm systems for left ventricular assist devices does not permit their implantation in eligible patients with visual impairment. We report two patients in whom the decrease in visual acuity was a significant factor in determining eligibility for long-term mechanical circulatory support., (© 2011 Expert Reviews Ltd)