Deprecated: bp_before_xprofile_cover_image_settings_parse_args is deprecated since version 6.0.0! Use bp_before_members_cover_image_settings_parse_args instead. in /home/top4art.com/public_html/wp-includes/functions.php on line 5094
  • Wiggins McKinney posted an update 20 hours, 8 minutes ago

    The long-term prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) is still unsatisfactory even after the emergence of tyrosine kinase inhibitors (TKIs) against chimeric BCR-ABL, and this is associated with the high incidence of genetic alterations of Ikaros family zinc finger 1 (IKZF1), most frequently the hemi-allelic loss of exons 4-7 expressing a dominant-negative isoform Ik6. We found that lenalidomide (LEN), a representative of immunomodulatory drugs (IMiDs), which have been long used for the treatment of multiple myeloma, specifically induced accumulation of Ik6 with the disappearance of functional isoforms within 24 h (i.e., abrupt and complete shut-down of the IKZF1 activity) in Ik6-positive Ph+ALL cells in a neddylation-dependent manner. The functional IKZF3 isoforms expression was also abruptly and markedly downregulated. The LEN treatment specifically suppressed proliferation of Ik6-positive-Ph+ALL cells by inducing cell cycle arrest via downregulation of cyclins Dly for those who are not tolerable to intensified therapeutic approaches.Dual specificity tyrosine phosphorylation regulated kinase 1A, DYRK1A, functions in multiple cellular pathways, including signaling, endocytosis, synaptic transmission, and transcription. Alterations in dosage of DYRK1A leads to defects in neurogenesis, cell growth, and differentiation, and may increase the risk of certain cancers. DYRK1A localizes to a number of subcellular structures including vesicles where it is known to phosphorylate a number of proteins and regulate vesicle biology. However, the mechanism by which it translocates to vesicles is poorly understood. Here we report the discovery of TRAF2, an E3 ligase, as an interaction partner of DYRK1A. Our data suggest that TRAF2 binds to PVQE motif residing in between the PEST and histidine repeat domain (HRD) of DYRK1A protein, and mediates K63-linked ubiquitination of DYRK1A. This results in translocation of DYRK1A to the vesicle membrane. DYRK1A increases phosphorylation of Sprouty 2 on vesicles, leading to the inhibition of EGFR degradation, and depletion of TRAF2 expression accelerates EGFR degradation. Further, silencing of DYRK1A inhibits the growth of glioma cells mediated by TRAF2. Collectively, these findings suggest that the axis of TRAF2-DYRK1A-Sprouty 2 can be a target for new therapeutic development for EGFR-mediated human pathologies.The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in an unprecedented setback for global economy and health. SARS-CoV-2 has an exceptionally high level of transmissibility and extremely broad tissue tropism. BRD0539 solubility dmso However, the underlying molecular mechanism responsible for sustaining this degree of virulence remains largely unexplored. In this article, we review the current knowledge and crucial information about how SARS-CoV-2 attaches on the surface of host cells through a variety of receptors, such as ACE2, neuropilin-1, AXL, and antibody-FcγR complexes. We further explain how its spike (S) protein undergoes conformational transition from prefusion to postfusion with the help of proteases like furin, TMPRSS2, and cathepsins. We then review the ongoing experimental studies and clinical trials of antibodies, peptides, or small-molecule compounds with anti-SARS-CoV-2 activity, and discuss how these antiviral therapies targeting host-pathogen interaction could potentially suppress viral attachment, reduce the exposure of fusion peptide to curtail membrane fusion and block the formation of six-helix bundle (6-HB) fusion core. Finally, the specter of rapidly emerging SARS-CoV-2 variants deserves a serious review of broad-spectrum drugs or vaccines for long-term prevention and control of COVID-19 in the future.We report the discovery of strong HNF4α agonists and their use to uncover a previously unknown pathway by which HNF4α controls the level of fat storage in the liver. This involves the induction of lipophagy by dihydroceramides, the synthesis and secretion of which is controlled by genes induced by HNF4α. The HNF4α activators are N-trans caffeoyltyramine (NCT) and N-trans feruloyltyramine (NFT), which are structurally related to the known drugs alverine and benfluorex, which we previously showed to be weak HNF4α activators. In vitro, NCT and NFT induced fat clearance from palmitate-loaded cells. In DIO mice, NCT led to recovery of hepatic HNF4α expression and reduction of steatosis. Mechanistically, increased dihydroceramide production and action downstream of HNF4α occurred through increased expression of HNF4α downstream genes, including SPNS2 and CYP26A1. NCT was completely nontoxic at the highest dose administered and so is a strong candidate for an NAFLD therapeutic.Arpp19 is a potent PP2A-B55 inhibitor that regulates this phosphatase to ensure the stable phosphorylation of mitotic/meiotic substrates. At G2-M, Arpp19 is phosphorylated by the Greatwall kinase on S67. This phosphorylated Arpp19 form displays a high affinity to PP2A-B55 and a slow dephosphorylation rate, acting as a competitor of PP2A-B55 substrates. The molecular determinants conferring slow dephosphorylation kinetics to S67 are unknown. PKA also phosphorylates Arpp19. This phosphorylation performed on S109 is essential to maintain prophase I-arrest in Xenopus oocytes although the underlying signalling mechanism is elusive. Here, we characterize the molecular determinants conferring high affinity and slow dephosphorylation to S67 and controlling PP2A-B55 inhibitory activity of Arpp19. Moreover, we show that phospho-S109 restricts S67 phosphorylation by increasing its catalysis by PP2A-B55. Finally, we discover a double feed-back loop between these two phospho-sites essential to coordinate the temporal pattern of Arpp19-dependent PP2A-B55 inhibition and Cyclin B/Cdk1 activation during cell division.Kindlin-2 is known to play important roles in the development of mesoderm-derived tissues including myocardium, smooth muscle, cartilage and blood vessels. However, nothing is known for the role of Kindlin-2 in mesoderm-derived reproductive organs. Here, we report that loss of Kindlin-2 in Sertoli cells caused severe testis hypoplasia, abnormal germ cell development and complete infertility in male mice. Functionally, loss of Kindlin-2 inhibits proliferation, increases apoptosis, impairs phagocytosis in Sertoli cells and destroyed the integration of blood-testis barrier structure in testes. Mechanistically, Kindlin-2 interacts with LATS1 and YAP, the key components of Hippo pathway. Kindlin-2 impedes LATS1 interaction with YAP, and depletion of Kindlin-2 enhances LATS1 interaction with YAP, increases YAP phosphorylation and decreases its nuclear translocation. For clinical relevance, lower Kindlin-2 expression and decreased nucleus localization of YAP was found in SCOS patients. Collectively, we demonstrated that Kindlin-2 in Sertoli cells is essential for sperm development and male reproduction.

Facebook Pagelike Widget

Who’s Online

Profile picture of Nikolajsen Munkholm
Profile picture of Comfort women
Profile picture of Molina Moon
Profile picture of Huff Bruhn
Profile picture of Torp Pace
Profile picture of Hvidberg Lin
Profile picture of Hart Conner
Profile picture of French England
Profile picture of Ballard Leslie
Profile picture of Pickett Boje
Profile picture of Mcpherson Dahl
Profile picture of Acevedo Middleton
Profile picture of Kofoed Ellison
Profile picture of Phillips Walther
Profile picture of McAllister Tychsen