Spatial resolution of two bacterial cell division proteins: ZapA recruits ZapB to the inner face of the Z-ring

TY - JOUR

T1 - Spatial resolution of two bacterial cell division proteins

T2 - ZapA recruits ZapB to the inner face of the Z-ring

AU - Galli, Elisa

AU - Gerdes, Kenn

PY - 2010/6

Y1 - 2010/6

N2 - Summary FtsZ, the essential regulator of bacterial cell division, is a dynamic cytoskeletal protein that forms helices that condense into the Z-ring prior to division. Two small coiled-coil proteins, ZapA and ZapB, are both recruited early to the Z-ring. We show here that ZapB is recruited to the Z-ring by ZapA. A direct interaction between ZapA and ZapB is supported by bacterial two-hybrid and in vitro interaction assays. Using high-resolution 3-D reconstruction microscopy, we find that, surprisingly, ZapB is located inside the Z-ring in virtually all cells investigated. We propose a molecular model in which ZapA increases lateral interactions between FtsZ proto-filaments and ZapB mediates further stabilization of this interaction by cross-linking ZapA molecules bound to adjacent FtsZ proto-filaments. Gene deletion and complementation assays show that ZapB can mitigate cell division and Z-ring assembly defects even in the absence of ZapA, raising the possibility that ZapB stimulates Z-ring assembly by two different mechanisms.

AB - Summary FtsZ, the essential regulator of bacterial cell division, is a dynamic cytoskeletal protein that forms helices that condense into the Z-ring prior to division. Two small coiled-coil proteins, ZapA and ZapB, are both recruited early to the Z-ring. We show here that ZapB is recruited to the Z-ring by ZapA. A direct interaction between ZapA and ZapB is supported by bacterial two-hybrid and in vitro interaction assays. Using high-resolution 3-D reconstruction microscopy, we find that, surprisingly, ZapB is located inside the Z-ring in virtually all cells investigated. We propose a molecular model in which ZapA increases lateral interactions between FtsZ proto-filaments and ZapB mediates further stabilization of this interaction by cross-linking ZapA molecules bound to adjacent FtsZ proto-filaments. Gene deletion and complementation assays show that ZapB can mitigate cell division and Z-ring assembly defects even in the absence of ZapA, raising the possibility that ZapB stimulates Z-ring assembly by two different mechanisms.

U2 - 10.1111/j.1365-2958.2010.07183.x

DO - 10.1111/j.1365-2958.2010.07183.x

M3 - Journal article

C2 - 20487275

SN - 0950-382X

VL - 76

SP - 1514

EP - 1526

JO - Molecular Microbiology

JF - Molecular Microbiology

IS - 6

ER -