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The tapetal AHL family protein TEK determines nexine formation in the pollen wall.

ABSTRACT: The pollen wall, an essential structure for pollen function, consists of two layers, an inner intine and an outer exine. The latter is further divided into sexine and nexine. Many genes involved in sexine development have been reported, in which the MYB transcription factor Male Sterile 188 (MS188) specifies sexine in Arabidopsis. However, nexine formation remains poorly understood. Here we report the knockout of TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK (TEK) leads to nexine absence in Arabidopsis. TEK encodes an AT-hook nuclear localized family protein highly expressed in tapetum during the tetrad stage. Absence of nexine in tek disrupts the deposition of intine without affecting sexine formation. We find that ABORTED MICROSPORES directly regulates the expression of TEK and MS188 in tapetum for the nexine and sexine formation, respectively. Our data show that a transcriptional cascade in the tapetum specifies the development of pollen wall.

SUBMITTER: Lou Y

PROVIDER: S-EPMC4024750 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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The tapetal AHL family protein TEK determines nexine formation in the pollen wall.

Lou Yue Y Xu Xiao-Feng XF Zhu Jun J Gu Jing-Nan JN Blackmore Stephen S Yang Zhong-Nan ZN

Nature communications 20140508

The pollen wall, an essential structure for pollen function, consists of two layers, an inner intine and an outer exine. The latter is further divided into sexine and nexine. Many genes involved in sexine development have been reported, in which the MYB transcription factor Male Sterile 188 (MS188) specifies sexine in Arabidopsis. However, nexine formation remains poorly understood. Here we report the knockout of TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK (TEK) leads to nexine absence in Arabido ...[more]

PMID: 24804694

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