- 作者: Adelfia Talà, Flora Guerra, Matteo Calcagnile, Roberta Romano, Silvia Caterina Resta, Aurora Paiano, Mario Chiariello, Graziano Pizzolante, Cecilia Bucci & Pietro Alifano
- 作者服務機構: 1.Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy 2.Core Research Laboratory-Siena, Institute for Cancer Research and Prevention (ISPRO), 53100, Siena, Italy 3.Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Via Provinciale Monteroni n. 165, 73100, Lecce, Italy 4.Institute of Clinical Physiology (IFC), National Research Council (CNR), 53100, Siena, Italy
- 中文摘要:
- 英文摘要:
Background: In Neisseria meningitidis the HrpA/HrpB two-partner secretion system (TPS) was implicated in diverse
functions including meningococcal competition, bioflm formation, adherence to epithelial cells, intracellular survival
and vacuolar escape. These diverse functions could be attributed to distinct domains of secreted HrpA.
Methods: A yeast two-hybrid screening, in vitro pull-down assay and immunofuorescence microscopy experiments
were used to investigate the interaction between HrpA and the dynein light-chain, Tctex-type 1 (DYNLT1). In silico
modeling was used to analyze HrpA structure. Western blot analysis was used to investigate apoptotic and pyroptotic
markers.
Results: The HrpA carboxy-terminal region acts as a manganese-dependent cell lysin, while the results of a yeast
two-hybrid screening demonstrated that the HrpA middle region has the ability to bind the dynein light-chain, Tctextype 1 (DYNLT1). This interaction was confrmed by in vitro pull-down assay and immunofuorescence microscopy
experiments showing co-localization of N. meningitidis with DYNLT1 in infected epithelial cells. In silico modeling
revealed that the HrpA-M interface interacting with the DYNLT1 has similarity with capsid proteins of neurotropic
viruses that interact with the DYNLT1. Indeed, we found that HrpA plays a key role in infection of and meningococcal trafcking within neuronal cells, and is implicated in the modulation of the balance between apoptosis and
pyroptosis.
Conclusions: Our fndings revealed that N. meningitidis is able to efectively infect and survive in neuronal cells, and
that this ability is dependent on HrpA, which establishes a direct protein–protein interaction with DYNLTI in these
cells, suggesting that the HrpA interaction with dynein could be fundamental for N. meningitidis spreading inside the
neurons. Moreover, we found that the balance between apoptotic and pyroptotic pathways is heavily afected by
HrpA. - 中文關鍵字:
- 英文關鍵字: : Host–pathogen interaction, Dynein, Apoptosis, Pyroptosis, Cell death, Bacteria, Two-hybrid system