A VPE-like protease NtTPE8 exclusively expresses in the integumentary tapetum and is involved in seed development
A VPE-like protease NtTPE8 exclusively expresses in the integumentary tapetum and is involved in seed development
复制标题
VPE 样蛋白酶 NtTPE8 只在外皮绒毡层中表达并参与种子发育
DOI：
10.1111/jipb.12766
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发表时间：
2019-05-01
影响因子：
11.4
通讯作者：
Sun, Meng-Xiang
中科院分区：
文献类型：
--
作者：
Wang, Wei;Xiong, Hanxian;Sun, Meng-Xiang
Programmed cell death (PCD) is an essential process for development, and shows conserved cytological features in both plants and animals. Caspases are well-known critical components of the PCD machinery in animals. However, currently few typical counterparts have been identified in plants and only several caspase-like proteases are known to be involved in plant PCD, indicating the existence of great challenge for confirming new caspase-like proteases and elucidating the mechanisms regulating plant PCD. Here, we report a novel cysteine protease, NtTPE8, which was extracted from tobacco seeds and confirmed as a new caspase-like protease. Recombinant NtTPE8 exhibited legumain and caspase-like proteolytic activities, both of which could be inhibited by the pan-caspase inhibitor (Z-VAD-FMK). Notably, NtTPE8 possessed several caspase activities and the capacity to cleave the cathepsin H substrate FVR, indicating a unique character of NtTPE8. NtTPE8 was exclusively expressed in the integumentary tapetum and thus, is the first specific molecular marker reported to date for this cell type. Down-regulation of NtTPE8 caused seed abortion, via disturbing early embryogenesis, indicating its critical role in embryogenesis and seed development. In conclusion, we identified a novel caspase-like cysteine protease, NtTPE8, exclusively expressed in the integumentary tapetum that is involved in seed development.
