Arabidopsis JANUS Regulates Embryonic Pattern Formation through Pol II-Mediated Transcription of WOX2 and PIN7

Feng Xiong; Hai-Hong Liu; Cun-Ying Duan; Bi-Ke Zhang; Guo Wei; Yan Zhang; Sha Li

doi:10.1016/j.isci.2019.09.004

Arabidopsis JANUS Regulates Embryonic Pattern Formation through Pol II-Mediated Transcription of WOX2 and PIN7

iScience. 2019 Sep 27:19:1179-1188. doi: 10.1016/j.isci.2019.09.004. Epub 2019 Sep 9.

Authors

Feng Xiong¹, Hai-Hong Liu¹, Cun-Ying Duan¹, Bi-Ke Zhang¹, Guo Wei¹, Yan Zhang¹, Sha Li²

Affiliations

¹ State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China.
² State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China; Department of Plant Biology and Ecology, College of Life Sciences, Nankai University, Tianjin, China. Electronic address: shali@sdau.edu.cn.

Abstract

Embryonic pattern formation relies on positional coordination of cell division and specification. Early axis formation during Arabidopsis embryogenesis requires WUSCHEL RELATED HOMEOBOX (WOX)-mediated transcription activation and PIN-FORMED7 (PIN7)-mediated auxin asymmetry. How these events are regulated is obscure. We report that Arabidopsis JANUS, a putative subunit of spliceosome, is essential for embryonic pattern formation. Significantly reduced transcription but not mRNA processing of WOX2 and PIN7 in janus suggested its role in transcriptional regulation. JANUS interacts with RNA polymerase II (Pol II) through a region outside of its spliceosome-association domain. We further show that Pol II mediates the transcription of WOX2 and PIN7 in a JANUS-dependent way and is essential for embryonic pattern formation. These findings reveal that JANUS recruits Pol II for the activation of two parallel pathways to ensure proper pattern formation during embryogenesis.

Keywords: Biological Sciences; Molecular Biology; Plant Biology; Plant Development.