Publications by authors named "Usman Hyder"

Signal-induced transcriptional programs regulate critical biological processes through the precise spatiotemporal activation of Immediate Early Genes (IEGs); however, the mechanisms of transcription induction remain poorly understood. By combining an acute depletion system with several genomics approaches to interrogate synchronized, temporal transcription, we reveal that KAP1/TRIM28 is a first responder that fulfills the temporal and heightened transcriptional demand of IEGs. Acute KAP1 loss triggers an increase in RNA polymerase II elongation kinetics during early stimulation time points.

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Article Synopsis
  • * Acute loss of KAP1 leads to faster RNA polymerase II elongation at first, but causes problems later in the transcription cycle, disrupting normal gene activation.
  • * KAP1 surprisingly acts to negatively regulate transcription elongation, which is essential for maintaining proper transcription levels of important genes in cells and organisms.
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HIV-1 latency remains a barrier to a functional cure because of the ability of virtually silent yet inducible proviruses within reservoir cells to transcriptionally reactivate upon cell stimulation. HIV-1 reactivation occurs through the sequential action of host transcription factors (TFs) during the "host phase" and the viral TF Tat during the "viral phase", which together facilitate the positive feedback loop required for exponential transcription, replication, and pathogenesis. The sequential action of these TFs poses a challenge to precisely delineate the contributions of the host and viral phases of the transcriptional program to guide future mechanistic and therapeutic studies.

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HIV-1 latency maintenance and reactivation are regulated by several viral and host factors. One such factor is Krüppel-associated box (KRAB)-associated protein 1 (KAP1: also named TRIM28 or TIF1β). While initial studies have revealed KAP1 to be a positive regulator of latency reversal in transformed and primary CD4 T cells, subsequent studies have proposed KAP1 to be a repressor required for latency maintenance.

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Several transcriptional and epigenetic regulators have been functionally linked to the control of viral and cellular gene expression programs. One such regulator is Krüppel-associated box (KRAB)-associated protein 1 (KAP1: also named TRIM28 or TIF1β), which has been extensively studied in the past three decades. Here we offer an up-to date review of its various functions in a diversity of contexts.

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Background: Contraceptive use is internationally endorsed as a human right and an indicator of the highest standard of sexual and reproductive health life. But reports from countries including Ethiopia showed a lower and capricious rate due to wider factors. Thus, the current study aimed to determine the prevalence and the predictors of contraceptive use among women of the premenopausal period.

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Inducible transcriptional programs mediate the regulation of key biological processes and organismal functions. Despite their complexity, cells have evolved mechanisms to precisely control gene programs in response to environmental cues to regulate cell fate and maintain normal homeostasis. Upon stimulation with proinflammatory cytokines such as tumor necrosis factor-α (TNF), the master transcriptional regulator nuclear factor (NF)-κB utilizes the PPM1G/PP2Cγ phosphatase as a coactivator to normally induce inflammatory and cell survival programs.

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Precise control of the RNA polymerase II (RNA Pol II) cycle, including pausing and pause release, maintains transcriptional homeostasis and organismal functions. Despite previous work to understand individual transcription steps, we reveal a mechanism that integrates RNA Pol II cycle transitions. Surprisingly, KAP1/TRIM28 uses a previously uncharacterized chromatin reader cassette to bind hypo-acetylated histone 4 tails at promoters, guaranteeing continuous progression of RNA Pol II entry to and exit from the pause state.

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Penetrating neck and chest injuries are a common form of occupational injuries. We hereby report a unique case in which a metallic rod had penetrated the left chest and neck of a plastic factory worker. The patient was vitally stable when he presented to Emergency Room.

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Background Aims: Cell replacement therapy is considered a promising alternative in the treatment of degenerative diseases, and in this context, mesenchymal stromal cells (MSCs) have been proposed for transplantation in Parkinson disease (PD). Thus far, the results of animal studies are found to be inconsistent and inconclusive regarding the therapeutic ability of the cells. This study investigated the efficacy of fetal liver (FL)-MSC-derived dopaminergic (DA) neuronal primed cells for correction of parkinsonian symptoms in mice.

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Besides their role in the generation of action potentials, voltage-gated potassium channels are implicated in cellular processes ranging from cell division to cell death. The K(+) channel regulator protein (KCNRG), identified as a putative tumor suppressor, reduces K(+) currents through human K(+) channels hKv1.1 and hKv1.

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Fast inactivation in voltage-gated potassium channels has traditionally been associated exclusively with the N-terminus. Here, we explore the role of the T1 domain using a series of chimeric channels. A chimeric channel, 4N/2, (N-terminus from the rapidly inactivating hKv1.

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