TY  - JOUR
A1  - Wagner, Fabienne
A1  - Kunz, Tobias C.
A1  - Chowdhury, Suvagata R.
A1  - Thiede, Bernd
A1  - Fraunholz, Martin
A1  - Eger, Debora
A1  - Kozjak-Pavlovic, Vera
T1  - Armadillo repeat-containing protein 1 is a dual localization protein associated with mitochondrial intermembrane space bridging complex
JF  - PLoS ONE
N2  - Cristae architecture is important for the function of mitochondria, the organelles that play the central role in many cellular processes. The mitochondrial contact site and cristae organizing system (MICOS) together with the sorting and assembly machinery (SAM) forms the mitochondrial intermembrane space bridging complex (MIB), a large protein complex present in mammalian mitochondria that partakes in the formation and maintenance of cristae. We report here a new subunit of the mammalian MICOS/MIB complex, an armadillo repeat-containing protein 1 (ArmC1). ArmC1 localizes both to cytosol and mitochondria, where it associates with the outer mitochondrial membrane through its carboxy-terminus. ArmC1 interacts with other constituents of the MICOS/MIB complex and its amounts are reduced upon MICOS/MIB complex depletion. Mitochondria lacking ArmC1 do not show defects in cristae structure, respiration or protein content, but appear fragmented and with reduced motility. ArmC1 represents therefore a peripheral MICOS/MIB component that appears to play a role in mitochondrial distribution in the cell.
KW  - Mitochondria
KW  - Outer membrane proteins
KW  - HeLa cells
KW  - Immunoprecipitation
KW  - Cytosol
KW  - Small interfering RNAs
KW  - Confocal microscopy
KW  - Cell stainin
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202670
VL  - 14
IS  - 10
ER  - 
TY  - JOUR
A1  - Prusty, Bhupesh K.
A1  - Chowdhury, Suvagata R.
A1  - Gulve, Nitish
A1  - Rudel, Thomas
T1  - Peptidase Inhibitor 15 (PI15) Regulates Chlamydial CPAF Activity
JF  - Frontiers in Cellular and Infection Microbiology
N2  - Obligate intracellular pathogenic Chlamydia trachomatis express several serine proteases whose roles in chlamydial development and pathogenicity are not completely understood. The chlamydial protease CPAF is expressed during the replicative phase of the chlamydial developmental cycle and is secreted into the lumen of the Chlamydia-containing vacuole called inclusion. How the secreted protease is activated in the inclusion lumen is currently not fully understood. We have identified human serine peptidase inhibitor PI15 as a potential host factor involved in the regulation of CPAF activation. Silencing expression as well as over expression of PI15 affected normal development of Chlamydia. PI15 was transported into the chlamydial inclusion lumen where it co-localized with CPAF aggregates. We show that PI15 binds to the CPAF zymogen and potentially induces CPAF protease activity at low concentrations. However, at high concentrations PI15 inhibits CPAF activity possibly by blocking its protease domain. Our findings shed light on a new aspect of chlamydial host co-evolution which involves the recruitment of host cell proteins into the inclusion to control the activation of bacterial proteases like CPAF that are important for the normal development of Chlamydia.
KW  - chlamydia
KW  - CPAF activation
KW  - peptidase inhibitor PI15
KW  - chlamydial inclusion
KW  - chlamydia serine proteases
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196918
SN  - 2235-2988
VL  - 8
IS  - 183
ER  -