βVPE is involved in tapetal degradation and pollen development by activating proprotease maturation in Arabidopsis thaliana

Cheng, Z.; Yin, B.; Zhang, J.; Liu, Y.; Wang, B.; Li, H.; Lu, H.

doi:10.1101/503508

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bioRxiv · 10.1101/503508

βVPE is involved in tapetal degradation and pollen development by activating proprotease maturation in Arabidopsis thaliana

Cheng, Z.·Yin, B.·Zhang, J.·Liu, Y.·Wang, B.·Li, H.·Lu, H.

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Abstract

Vacuolar processing enzyme (VPE) is responsible for the maturation and activation of vacuolar proteins in plants. We found that {beta}VPE was involved in tapetal degradation and pollen development by transforming proproteases into mature protease in Arabidopsis thaliana. {beta}VPE was expressed specifically in the tapetum from stages 5-8 of anther development. The {beta}VPE protein first appeared as a proenzyme and transformed into the mature enzyme before stages 7-8. The recombinant {beta}VPE protein self-cleaved and transformed to a 27-kD mature protein at pH 5.2. The mature {beta}VPE protein could induce the maturation of CEP1 in vitro. {beta}vpe mutants exhibited delayed vacuolar degradation and decreased pollen fertility. The maturation of CEP1, RD19A, and RD19C were seriously inhibited in {beta}vpe mutants. Our results indicate that {beta}VPE is a crucial processing enzyme that directly participates in the maturation of cysteine proteases before vacuolar degradation, and is indirectly involved in pollen development and tapetal cell degradation.\n\nHighlight{beta}VPE is a crucial processing enzyme that directly participates in the maturation of cysteine proteases before vacuolar degradation, and is indirectly involved in pollen development and tapetal cell degradation.

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Cheng, Z., Yin, B., Zhang, J., Liu, Y., Wang, B., Li, H., Lu, H.. 2018-12-21. βVPE is involved in tapetal degradation and pollen development by activating proprotease maturation in Arabidopsis thaliana. https://doi.org/10.1101/503508

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