International Journal of Research in Medical Sciences, 2014
We studied seven cases of Hantavirus infection and renal involvement who presented at our institu... more We studied seven cases of Hantavirus infection and renal involvement who presented at our institute in last 4 months. Their demographic profile and presenting ABSTRACT Background: Hantavirus infections are found all over world but there is paucity of information about clinical features of Hantavirus infection in India. Aim of current study was to study clinical profile and outcome of patients with Hantavirus infection and renal insufficiency who presented at our institute. Methods: All patients who were admitted in department of medicine with Hantavirus infection and renal insufficiency were included. Their basic demographic profile with relevant laboratory investigations was recorded. They were diagnosed with Hantavirus infection if they had positive IgM antibodies by ELISA test. Results: There were seven patients with mean age of 54 years. They had mean serum creatinine level of 4.37 ± 1.86 mg%. All had thrombocytopenia and hepatic dysfunction as well. Five patients had hypotension. There was need of dialysis in three patients. They also had hypoalbuminemia. No patient had features suggestive of acute respiratory distress syndrome. All patients had recovery of renal function and there was no mortality. Conclusion: Patients with Hantavirus infection presented like hemorrhagic fever with renal syndrome. Their outcome is good. We need to suspect Hantavirus infection in appropriate clinical scenario in India.
The SLIP1-SLBP complex activates translation of replication-dependent histone mRNAs. In this repo... more The SLIP1-SLBP complex activates translation of replication-dependent histone mRNAs. In this report, we describe how the activity of the SLIP1-SLBP complex is modulated by phosphorylation and oligomerization. Biophysical characterization of the free proteins shows that whereas SLIP1 is a homodimer that does not bind RNA, human SLBP is an intrinsically disordered protein that is phosphorylated at 23 Ser/Thr sites when expressed in a eukaryotic expression system such as baculovirus. The bacterially expressed unphosphorylated SLIP1-SLBP complex forms a 2:2 high-affinity (K(D) < 0.9 nM) heterotetramer that is also incapable of binding histone mRNA. In contrast, phosphorylated SLBP from baculovirus has a weak affinity (K(D) ~3 μM) for SLIP1. Sequential binding of phosphorylated SLBP to the histone mRNA stem-loop motif followed by association with SLIP1 is required to form an "active" ternary complex. Phosphorylation of SLBP at Thr171 promotes dissociation of the heterotetramer to the SLIP1-SLBP heterodimer. Using alanine scanning mutagenesis, we demonstrate that the binding site on SLIP1 for SLBP lies close to the dimer interface. A single-point mutant near the SLIP1 homodimer interface abolished interaction with SLBP in vitro and reduced the abundance of histone mRNA in vivo. On the basis of these biophysical studies, we propose that oligomerization and SLBP phosphorylation may regulate the SLBP-SLIP1 complex in vivo. SLIP1 may act to sequester SLBP in vivo, protecting it from proteolytic degradation as an inactive heterotetramer, or alternatively, formation of the SLIP1-SLBP heterotetramer may facilitate removal of SLBP from the histone mRNA prior to histone mRNA degradation.
International Journal of Research in Medical Sciences, 2014
We studied seven cases of Hantavirus infection and renal involvement who presented at our institu... more We studied seven cases of Hantavirus infection and renal involvement who presented at our institute in last 4 months. Their demographic profile and presenting ABSTRACT Background: Hantavirus infections are found all over world but there is paucity of information about clinical features of Hantavirus infection in India. Aim of current study was to study clinical profile and outcome of patients with Hantavirus infection and renal insufficiency who presented at our institute. Methods: All patients who were admitted in department of medicine with Hantavirus infection and renal insufficiency were included. Their basic demographic profile with relevant laboratory investigations was recorded. They were diagnosed with Hantavirus infection if they had positive IgM antibodies by ELISA test. Results: There were seven patients with mean age of 54 years. They had mean serum creatinine level of 4.37 ± 1.86 mg%. All had thrombocytopenia and hepatic dysfunction as well. Five patients had hypotension. There was need of dialysis in three patients. They also had hypoalbuminemia. No patient had features suggestive of acute respiratory distress syndrome. All patients had recovery of renal function and there was no mortality. Conclusion: Patients with Hantavirus infection presented like hemorrhagic fever with renal syndrome. Their outcome is good. We need to suspect Hantavirus infection in appropriate clinical scenario in India.
The SLIP1-SLBP complex activates translation of replication-dependent histone mRNAs. In this repo... more The SLIP1-SLBP complex activates translation of replication-dependent histone mRNAs. In this report, we describe how the activity of the SLIP1-SLBP complex is modulated by phosphorylation and oligomerization. Biophysical characterization of the free proteins shows that whereas SLIP1 is a homodimer that does not bind RNA, human SLBP is an intrinsically disordered protein that is phosphorylated at 23 Ser/Thr sites when expressed in a eukaryotic expression system such as baculovirus. The bacterially expressed unphosphorylated SLIP1-SLBP complex forms a 2:2 high-affinity (K(D) < 0.9 nM) heterotetramer that is also incapable of binding histone mRNA. In contrast, phosphorylated SLBP from baculovirus has a weak affinity (K(D) ~3 μM) for SLIP1. Sequential binding of phosphorylated SLBP to the histone mRNA stem-loop motif followed by association with SLIP1 is required to form an "active" ternary complex. Phosphorylation of SLBP at Thr171 promotes dissociation of the heterotetramer to the SLIP1-SLBP heterodimer. Using alanine scanning mutagenesis, we demonstrate that the binding site on SLIP1 for SLBP lies close to the dimer interface. A single-point mutant near the SLIP1 homodimer interface abolished interaction with SLBP in vitro and reduced the abundance of histone mRNA in vivo. On the basis of these biophysical studies, we propose that oligomerization and SLBP phosphorylation may regulate the SLBP-SLIP1 complex in vivo. SLIP1 may act to sequester SLBP in vivo, protecting it from proteolytic degradation as an inactive heterotetramer, or alternatively, formation of the SLIP1-SLBP heterotetramer may facilitate removal of SLBP from the histone mRNA prior to histone mRNA degradation.
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Papers by Nitin Bansal