Host cell RNA polymerase II-mediated transcription is inhibited by poliovirus infection. Previous studies from our laboratory showed that activated transcription from a cyclic AMP-responsive element (CRE)containing promoter was severely inhibited in extracts prepared from poliovirus-infected HeLa cells compared to those from mock-infected cells. Here we demonstrate that the CRE-binding protein, CREB, is specifically cleaved by the poliovirus-encoded protease 3C pro both in vitro and in virus-infected cells. The proteolytic cleavage of CREB leads to a significant loss of its DNA binding as well as transcriptional activity. Additionally, we demonstrate that the phosphorylated, transcriptionally active form of CREB is cleaved by the viral protease in vitro. The results presented here suggest that a direct cleavage of CREB by the viral protease 3C pro leads to inhibition of CREB-activated transcription in poliovirus-infected HeLa cells.Infection of susceptible cells with members of the picornavirus family results in the rapid inhibition of host cell RNA synthesis (18). Infection of HeLa cells with poliovirus, for example, causes a severe decrease in transcription catalyzed by RNA polymerase I (pol I), pol II, and pol III (1, 2, 18). It has been shown that the inhibition of transcription observed in vivo can be recapitulated in vitro by using extracts prepared from either mock-or poliovirus-infected HeLa cells (6). For each of the three polymerase systems, in vitro analysis has revealed that the inhibition of cellular transcription by poliovirus infection is a consequence of inactivation of specific transcription factors (11,20,28). Previous results from our laboratory have shown that the pol II transcription factor TFIID is inactivated in poliovirus-infected HeLa cells (20). More recently, we have shown that the TATA-binding protein (TBP), the DNA-binding subunit of TFIID, is proteolytically cleaved by the virusspecific protease 3C pro (3). This cleavage leads to a loss of formation of the TBP-TATA box complex in vitro (32). We have shown recently that both TATA-and initiator elementmediated basal transcription is inhibited by the viral protease (32). Similarly, a pol III DNA-binding transcription factor, TFIIIC, is cleaved and inactivated by 3C pro (4). The ␣ subunit of TFIIIC, which actually contacts the pol III promoter, is the target of the viral protease 3C pro (29). An unknown pol I transcription factor is also cleaved by the poliovirus protease, resulting in inhibition of pol I transcription in virus-infected cells (28).While the TATA or initiator elements carry out low-level (basal) transcription of many genes, high-level (activated) transcription of many cellular and viral promoters involves interaction of multiple upstream transcription factors. These elements have been found to be required for induction by exogenous substrates, such as phorbol esters, serum, and cyclic AMP (cAMP) (25). One such factor, the cAMP-responsive element (CRE)-binding protein, CREB, binds to DNA ele-ments required for induction by...

Cardiovascular disease is increased in individuals with type 1 or type 2 diabetes mellitus (DM). Left ventricular hypertrophy (LVH), which is an ominous prognostic sign and an independent risk factor for cardiac events, is often present in type 2 DM patients. The aim of our cross-sectional study was to evaluate the prevalence of LVH, and risk factors for its development, in normotensive type 2 diabetic patients without antihypertensive medication. The objectives of the study were to find out the prevalence of high left ventricular mass (LVM) in normotensive type 2 diabetic patients and compare it with nondiabetics and to uncover the risk factors for the development of high LVM in normotensive type 2 diabetic patients. A total of 130 age- and sex-matched subjects were selected (65 cases, diabetic normotensive, and 65 controls, nondiabetic normotensive) and baseline data were collected. LVM and left ventricular mass index (LVMI) were calculated using echocardigraphic parameters and body surface area. LVMI was significantly higher in patients with type 2 DM compared with age-, sex-matched healthy population (104.9 ± 21 vs. 78.5 ± 22.7 g/m2, respectively; P < 0.05). BMI, HbA1c, and duration of diabetes were significantly associated with LVH whereas sexes, age, PPBS, were not.

The poliovirus-encoded, membrane-associated VPg-precursor polypeptide 3AB has been implicated in the initiation of viral RNA synthesis. We have expressed 3AB and 3A polypeptides in eukaryotic cells and examined their localization using indirect immunofluorescence and a direct in vitro membrane-binding assay. Results presented here demonstrate that both 3AB and 3A are capable of localizing in the endoplasmic reticulum and the Golgi apparatus in transfected HeLa cells in the absence of any other poliovirus protein. We have also shown that the carboxy-terminal 18 amino acids of 3A that constitute an amphipathic domain are important in membrane binding of 3A and 3AB. Additionally, we demonstrate that a significant fraction of both 3A and 3AB can be glycosylated in a membrane-dependent fashion during in vitro translation in reticulocyte lysate. We demonstrate that 6-diazo-5-oxo-L-norleucine, an inhibitor of glycoprotein synthesis, significantly inhibits poliovirus RNA synthesis in vivo. The implications of glycosylation of 3AB (and 3A) in viral replication are discussed.

BackgroundHuman immunodeficiency virus (HIV) infection is associated with an increased risk for human herpes viruses (HHVs) and their related diseases and they frequently cause disease deterioration and therapeutic failures. Methods for limiting the transmission of HHVs require a better understanding of the incidence and infectivity of oral HHVs in HIV-infected patients. This study was designed to determine the seroprevalence of human herpes viruses (CMV, HSV 2, EBV-1, VZV) antibodies and to evaluate their association with age, sex as well as other demographic and behavioral factors.ResultsA study of 200 HIV positive patients from Eastern India attending the Calcutta Medical College Hospital, Kolkata, West Bengal, Apex Clinic, Calcutta Medical College Hospital and ART Center, School of Tropical Medicine, Kolkata, West Bengal was done. Serum samples were screened for antibodies to the respective viruses using the indirect ELISA in triplicates.CytoMegalo virus (CMV), Herpes Simplex virus type 2 (HSV-2), Varicella Zoster virus (VZV), and Epstein Barr virus (EBV-1) were detected in 49%, 47%, 32.5%, and 26% respectively.ConclusionThis study has contributed baseline data and provided insights in viral OI and HIV co-infection in Eastern India. This would undoubtedly serve as a basis for further studies on this topic.

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