Plant phytaspases and animal caspases: structurally unrelated death proteases with a common role and specificity

TY - JOUR

T1 - Plant phytaspases and animal caspases

T2 - structurally unrelated death proteases with a common role and specificity

AU - Chichkova, Nina V.

AU - Tuzhikov, Alexander I.

AU - Taliansky, Michael

AU - Vartapetian, Andrey B.

PY - 2012/5

Y1 - 2012/5

N2 - Proteases with an aspartate cleavage specificity are known to contribute to programmed cell death (PCD) in animals and plants. In animal cells this proteolytic activity belongs to caspases, a well-characterized family of cysteine-dependent death proteases. Plants, however, lack caspase homologs and thus the origin of this type of proteolytic activity in planta was poorly understood. Here, we review recent data demonstrating that a plant serine-dependent protease, phytaspase, shares cleavage specificity and a role in PCD analogous to that of caspases. However, unlike caspases, regulation of phytaspase-mediated cleavage of intracellular target proteins appears to be attained not at the level of proenzyme processing/activation, which occurs, in the case of phytaspase, autocatalytically and constitutively. Rather, the mature phytaspase is excluded from healthy cells into the apoplast and is allowed to re-enter cells upon the induction of PCD. Thus, PCD-related proteases in animals and plants display both common features and important distinctions.

AB - Proteases with an aspartate cleavage specificity are known to contribute to programmed cell death (PCD) in animals and plants. In animal cells this proteolytic activity belongs to caspases, a well-characterized family of cysteine-dependent death proteases. Plants, however, lack caspase homologs and thus the origin of this type of proteolytic activity in planta was poorly understood. Here, we review recent data demonstrating that a plant serine-dependent protease, phytaspase, shares cleavage specificity and a role in PCD analogous to that of caspases. However, unlike caspases, regulation of phytaspase-mediated cleavage of intracellular target proteins appears to be attained not at the level of proenzyme processing/activation, which occurs, in the case of phytaspase, autocatalytically and constitutively. Rather, the mature phytaspase is excluded from healthy cells into the apoplast and is allowed to re-enter cells upon the induction of PCD. Thus, PCD-related proteases in animals and plants display both common features and important distinctions.

U2 - 10.1111/j.1399-3054.2011.01560.x

DO - 10.1111/j.1399-3054.2011.01560.x

M3 - Article

C2 - 22182311

SN - 0031-9317

VL - 145

SP - 77

EP - 84

JO - Physiologia Plantarum

JF - Physiologia Plantarum

IS - 1

ER -