bims-actimu Biomed News
on Actinopathies in inborn errors of immunity
Issue of 2023‒11‒19
two papers selected by
Elodie Busch, University of Strasbourg

  1. J Cell Biol. 2024 Jan 01. pii: e202306154. [Epub ahead of print]223(1):
      Clathrin-mediated endocytosis depends on polymerization of a branched actin network to provide force for membrane invagination. A key regulator in branched actin network formation is actin capping protein (CP), which binds to the barbed end of actin filaments to prevent the addition or loss of actin subunits. CP was thought to stochastically bind actin filaments, but recent evidence shows CP is regulated by a group of proteins containing CP-interacting (CPI) motifs. Importantly, how CPI motif proteins function together to regulate CP is poorly understood. Here, we show Aim21 and Bsp1 work synergistically to recruit CP to the endocytic actin network in budding yeast through their CPI motifs, which also allosterically modulate capping strength. In contrast, twinfilin works downstream of CP recruitment, regulating the turnover of CP through its CPI motif and a non-allosteric mechanism. Collectively, our findings reveal how three CPI motif proteins work together to regulate CP in a stepwise fashion during endocytosis.
  2. Rev Soc Bras Med Trop. 2023 ;pii: S0037-86822023000100710. [Epub ahead of print]56 e03222023
      Visceral Leishmaniasis (VL) is a potentially fatal disease and may be associated with primary or acquired immunodeficiencies. There are few reports, in the literature, of inborn errors of immunity. Here, we report two cases of VL as a marker of inborn errors of immunity, namely, GATA2 and RAB27A deficiency. Our data suggest that VL patients should be screened for primary immunodeficiency, particularly in cases of VL relapse.