Actin dynamics regulation by TTC7A/PI4KIIIα limits DNA damage and cell death under confinement - 04/10/23

, Fernando E. Sepulveda, PhD a, b, k, ⁎ 
Graphical abstract |
Abstract |
Background |
The actin cytoskeleton has a crucial role in the maintenance of the immune homeostasis by controlling various cellular processes, including cell migration. Mutations in TTC7A have been described as the cause of a primary immunodeficiency associated to different degrees of gut involvement and alterations in the actin cytoskeleton dynamics.
Objectives |
This study investigates the impact of TTC7A deficiency in immune homeostasis. In particular, the role of the TTC7A/phosphatidylinositol 4 kinase type III α pathway in the control of leukocyte migration and actin dynamics.
Methods |
Microfabricated devices were leveraged to study cell migration and actin dynamics of murine and patient-derived leukocytes under confinement at the single-cell level.
Results |
We show that TTC7A-deficient lymphocytes exhibit an altered cell migration and reduced capacity to deform through narrow gaps. Mechanistically, TTC7A-deficient phenotype resulted from impaired phosphoinositide signaling, leading to the downregulation of the phosphoinositide 3-kinase/AKT/RHOA regulatory axis and imbalanced actin cytoskeleton dynamics. TTC7A-associated phenotype resulted in impaired cell motility, accumulation of DNA damage, and increased cell death in dense 3-dimensional gels in the presence of chemokines.
Conclusions |
These results highlight a novel role of TTC7A as a critical regulator of lymphocyte migration. Impairment of this cellular function is likely to contribute to the pathophysiology underlying progressive immunodeficiency in patients.
Il testo completo di questo articolo è disponibile in PDF.Key words : TTC7A, cell migration, actin dynamics, nuclear deformation, cell survival under confinement
Abbreviations used : 3D, ARP2/3, B-LCL, ctrl, DC, fsn, HD, iDC, mDC, mDia1, pAKT, PI3K, PI4KIIIα, PI4P
Mappa
Vol 152 - N° 4
P. 949-960 - ottobre 2023 Ritorno al numeroBenvenuto su EM|consulte, il riferimento dei professionisti della salute.
