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Vibhuti Rana,1 Nittu Singh,1 Chaitali Nikam,2 Priti Kambli,2 Pravin K Singh,3 Urmila Singh,3 Amita Jain,3 Camilla Rodrigues,2 Charu Sharma1 1CSIR- Institute of Microbial Technology, Chandigarh, 160036, India; 2Department of Microbiology, P. D. Hinduja National Hospital and Medical Research Centre, Mumbai, 400016, Maharashtra, India; 3Department of Microbiology, King George Medical University, Lucknow, 226003, Uttar Pradesh, IndiaCorrespondence: Charu Sharma, CSIR-Institute of Microbial Technology, Sector 39-A, Chandigarh, 160036, India, Tel +911722880309/310, Fax +911722690585, Email charu@imtech.res.inIntroduction: The mechanistic details of first line drug (FLD) resistance have been thoroughly explored but the genetic resistance mechanisms of second line injectables, which form the backbone of the combinatorial drug resistant tuberculosis therapy, are partially identified. This study aims to highlight the genetic and spoligotypic differences in the second line drug (SLD) resistant and sensitive Mycobacterium tuberculosis (Mtb) clinical isolates from Mumbai (Western India) and Lucknow (Northern India).Methods: The rrs, eis, whiB7, tlyA, gyrA and gyrB target loci were screened in 126 isolates and spoligotyped.Results: The novel mutations were observed in whiB7 loci (A43T, C44A, C47A, G48T, G59A and T152G in 5’-UTR; A42C, C253T and T270G in gene), tlyA (+CG200, G165A, C415G, and +G543) and gyrB (+G1359 and +A1429). Altogether, the rrs, eis, and whiB7 loci harbored mutations in ∼ 86% and ∼ 47% kanamycin resistant isolates from Mumbai and Lucknow, respectively. Mumbai strains displayed higher prevalence of mutations in gyrA (∼ 85%) and gyrB loci (∼ 13%) as compared to those from Lucknow (∼ 69% and ∼ 3.0%, respectively). Further, spoligotyping revealed that Beijing lineage is distributed equally amongst the drug resistant strains of Mumbai and Lucknow, but EAI-5 is existed at a higher level only in Mumbai. The lineages Manu2, CAS1-Delhi and T1 are more prevalent in Lucknow.Conclusion: Besides identifying novel mutations in whiB7, tlyA and gyrB target loci, our analyses unveiled a potential polymorphic and phylogeographical demarcation among two distinct regions.Keywords: drug resistant tuberculosis, single nucleotide polymorphism, rrs, eis, whiB7, spoligotyping

Condensin II subunits are known to be expressed and localized to interphase nuclei of eukaryotic cells. Although some studies have shown that condensin II likely exerts axial compaction forces, organizes chromosome territories, and has possible transcriptional modulatory functions, the full range of condensin II interphase activities are not known. In particular, it is not known if condensin II interphase activities are generally genome‐wide or if they have additional local activities unique to specific chromosomal structures such as telomeres. Here, we find that NCAPH2 interacts with TRF1 and these two proteins co‐localize at telomeres. Depletion of NCAPH2 leads to ATR‐dependent accumulation of 53BP1 and γH2AX DNA damage foci, including damage specific to telomeres. Furthermore, depletion of NCAPH2 results in a fragile telomere phenotype and apparent sister‐telomere fusions only days after NCAPH2 depletion. Taken together these observations suggest that NCAPH2 promotes telomere stability, possibly through a direct interaction with the TRF1 shelterin component, and prevents telomere dysfunction resulting from impaired DNA replication. Because proper telomere function is essential for chromosome integrity these observations reveal a previously unappreciated function for NCAPH2 in ensuring genome and telomere stability.

Condensin complexes exist across all domains of life and are central to the structure and organization of chromatin. As architectural proteins, condensins control chromatin compaction during interphase and mitosis. Condensin activity has been well studied in mitosis but have recently emerged as important regulators of genome organization and gene expression during interphase. Here, we focus our discussion on recent findings on the molecular mechanism and how condensins are used to shape chromosomes during interphase. These findings suggest condensin activity during interphase is required for proper chromosome organization. J. Cell. Physiol. 232: 1617-1625, 2017. © 2016 Wiley Periodicals, Inc.

Cognitive radio (CR) is the current growing technology in wireless communication field and has increase the ability to use the frequency spectrum more properly. The main objective of cognitive radios is to sense the surrounding and use primary user's vacant spaces and allot them to the secondary users without interference each other. This paper presents the optimal solution and optimizes the Quality of services (QoS) parameters to minimum i.e. smaller as compare other solutions which are induced by different optimization techniques Simulated Annealing (SA) and Genetic algorithm (GA). The proposed algorithm called spider monkey optimization algorithm (SMO). SMO is a swarm intelligence technique which works on foraging behaviour of spider monkeys. SMO is tentative and lapse based synergetic iterative process. Spider monkeys have been categorized as fusion-fission social structure (FHSS) based animals and they divides into smaller subgroups and search food. The proposed algorithm has been used to optimize the performance of QoS parameters in terms of minimum power consumption, minimum bit error rate (BER), maximum throughput, minimum interference and maximum spectral efficiency. The simulation results shows that the fitness scores obtained by the proposed algorithm i.e. SMO are better (smaller) than SA and GA algorithm in the optimization of QoS parameters of cognitive radio system. The proposed algorithm is better (smaller) than the existing algorithm.

Summary: Interaction domains in Drosophila chromosomes form by segregation of active and inactive chromatin in the absence of CTCF loops, but the role of transcription versus other architectural proteins in chromatin organization is unclear. Here, we find that positioning of RNAPII via transcription elongation is essential in the formation of gene loops, which in turn interact to form compartmental domains. Inhibition of transcription elongation or depletion of cohesin decreases gene looping and formation of active compartmental domains. In contrast, depletion of condensin II, which also localizes to active chromatin, causes increased gene looping, formation of compartmental domains, and stronger intra-chromosomal compartmental interactions. Condensin II has a similar role in maintaining inter-chromosomal interactions responsible for pairing between homologous chromosomes, whereas inhibition of transcription elongation or cohesin depletion has little effect on homolog pairing. The results suggest distinct roles for cohesin and condensin II in the establishment of 3D nuclear organization in Drosophila. : Using Hi-C analyses, Rowley et al. show that Drosophila genes form loops between the TSS and TTS, which in turn interact to form compartmental domains. Cohesin and condensin act in opposite ways on the formation of gene loops and domains. Keywords: CTCF, transcription, compartment, TAD, pairing, transvection, loop, Hi-C, HiChIP

Condensin complexes exist across all domains of life and are central to the structure and organization of chromatin. As architectural proteins, condensins control chromatin compaction during interphase and mitosis. Condensin activity has been well studied in mitosis but have recently emerged as important regulators of genome organization and gene expression during interphase. Here, we focus our discussion on recent findings on the molecular mechanism and how condensins are used to shape chromosomes during interphase. These findings suggest condensin activity during interphase is required for proper chromosome organization. J. Cell. Physiol. 232: 1617-1625, 2017. © 2016 Wiley Periodicals, Inc.

The Mycobacterium tuberculosis e xported r epetitive p rotein (RvErp) is a crucial virulence-associated factor as determined by its role in the survival and multiplication of mycobacteria in cultured macrophages and in vivo . Although attempts have been made to understand the function of Erp protein, its exact role in Mycobacterium pathogenesis is still elusive. One way to determine this is by searching for novel interactions of RvErp. Using a yeast two-hybrid assay, an adenylyl cyclase (AC), Rv2212, was found to interact with RvErp. The interaction between RvErp and Rv2212 is direct and occurs at the endogenous level. The Erp protein of Mycobacterium smegmatis (MSMEG_6405, or MsErp) interacts neither with Rv2212 nor with Ms_4279, the M. smegmatis homologue of Rv2212. Deletion mutants of Rv2212 revealed its adenylyl cyclase domain to be responsible for the interaction. RvErp enhances Rv2212-mediated cyclic AMP (cAMP) production. Also, the biological significance of the interaction between RvErp and Rv2212 was demonstrated by the enhanced survival of M. smegmatis within THP-1 macrophages. Taken together, these studies address a novel mechanism by which Erp executes its function. IMPORTANCE RvErp is one of the important virulence factors of M. tuberculosis . This study describes a novel function of RvErp protein of M. tuberculosis by identifying Rv2212 as its interacting protein. Rv2212 is an adenylyl cyclase (AC) and produces cAMP, one of the prime second messengers that regulate the intracellular survival of mycobacteria. Therefore, the significance of investigating novel interactions of RvErp is paramount in unraveling the mechanisms governing the intracellular survival of mycobacteria.

Twenty-nine Kanamycin resistant clinical isolates of Mycobacterium tuberculosis from Northern India were screened to evaluate genetic mutations in rrs gene, eis gene with its promoter, and whiB7 gene along with its 5'UTR. 14 strains (~48.0%) collectively exhibited mutations in rrs, eis or whiB7 target regions. While the highest frequency of mutations was found in rrs gene, eis and whiB7 loci displayed novel mutations. The novel mutations displayed by eis and whiB7 loci were found to be associated specifically with the Kanamycin resistance as none of the twenty nine Kanamycin sensitive strains harbor them. The inclusion of novel mutations of eis and whiB7 loci will be useful in improving the specificity of future diagnostics.