Rabbit Anti-Human CDK2 (phospho T160) polyclonal antibody

Midostaurin is a multi-kinase inhibitor with antineoplastic activity. We assessed the capacity of midostaurin to affect early and late steps of HIV-1 infection and to reactivate HIV-1 latently infected cells, alone or in combination with histone deacetylase inhibitors (HDACi) known to act as latency-reversing agents (LRA). Acute HIV-1 infection was assessed by flow cytometry in three cell types treated with midostaurin in the presence or absence of SAMHD1. Non-infected cells were treated with midostaurin and harvested for Western blot analysis. Macrophage infections were also measured by quantitative RT-PCR. HIV-1 latency reactivation was assessed in several latency models. Midostaurin induced G2/M arrest and inhibited CDK2, preventing the phosphorylation of SAMHD1 associated to inhibition of its dNTPase activity. In the presence of SAMHD1, midostaurin blocked HIV-1 DNA formation and viral replication. However, following Vpx-mediated SAMHD1 degradation, midostaurin increased viral transcripts and virus replication. In three out of four HIV-1 latency models, including primary CD4(+) T cells, midostaurin effectively reversed HIV-1 latency and was synergistic in combination with LRA vorinostat and panobinostat. Our study describes a dual effect for midostaurin in HIV-1 infection, antiviral or proviral depending on SAMHD1 activation, and highlights a role for active SAMHD1 in regulating the activity of potential HIV-1 latency reversal agents.

Kojic acid has significant anti-melanogenic activity in mammals. However, few reports showed its function and mechanism in bivalves. In this study, by survival rate investigation and colour identification, 0.2-5 g/L kojic acid treatment for 24-48 hr was verified to be safe and effective to lighten shell colour of Pteria penguin (Roding; 1798). The liquid chromatograph-tandem mass spectrometer (LC-MS/MS) analysis showed that the content of PDCA (pyrrole-2, 3-dicarboxylic acid) and PTCA (pyrrole-2,3,5-tricarboxylic acid), main alkaline oxidation products of eumelanin, were significantly decreased from 651.0 to 275.7 ng/mg (by 57.7%) after kojic acid treatment. Consistent with decrease in melanin content, the tyrosinase activity was also significantly inhibited by up to 54.7% in a dose-dependent and time-dependent manner. Different from the mammals, the qRT-PCR (quantitative real-time PCR) showed that kojic acid inhibited the expression of genes in tyrosinase pathway, including Tyr (Tyrosinase), Mitf (microphthalmia-associated transcription factor), Yel (Yellow) and Cdk2 (cyclin-dependent kinase 2), but had no effect on PpBcl2 (B-cell lymphoma 2). These data indicated that kojic acid changed shell colour by blocking tyrosinase activity and negatively regulating transcription of tyrosinase pathway genes in P. penguin. The effectiveness of kojic acid in modifying nacre colour suggested potential for its application in the aquaculture production of higher quality cultured pearls in P. penguin.