With so many new faces joining the Wagner lab over the last year, about half the lab has only known our lab meetings as virtual. However, now that all the members of the Wagner lab have been fully vaccinated, we can finally return to lab meetings in-person. While virtual meetings had their pros (its easier to see the minute details of a slide on your own computer) and cons (having to constantly monitor your mute button), having our first in-person lab meeting felt like an accomplishment that warranted a group selfie.
Senior at University of Pennsylvania, Adam Konkol, an undergraduate who worked in the Wagner lab, was awarded a Churchill Scholarship along with December graduate Abigail Timmel. Featured in PennToday, the Wagner Lab is excited to have been a part of Konkol’s journey and look forward to what the future has in store. For more information, see the PennToday article at: https://penntoday.upenn.edu/news/two-churchill-scholars-penn
The Wagner Lab is delighted to receive yet another fantastic addition to our team. Dr. Sarah Matar joins us after defending her PhD thesis on the vernalization-driven transition to flowering in winter rapeseed in the lab of Dr. Christian Jung of the Plant breeding institute in Kiel University in Germany. In the Wagner Lab, we look forward to her work on understanding the antagonistic roles of FT and TFL1.
This Valentines Day weekend the Wagner Lab welcomed the newest member of our lab, Dr. Sandhan Prakash, to the City of Brotherly Love! Dr. Prakash flew all the way from the Indian Institute of Science (IISc) in Bangalore, India where he received his Ph.D. In the Wagner Lab, he plans to study the function of epigenomic regulators in cell fate reprogramming and plant survival mechanism during abiotic stress response.
The Wagner Lab’s most recent publication uncovers the role of a protein called “LFY” in Arabidopsis chromatin regulation. A news release on the publication was covered by the American Association for the Advancement of Science (AAAS). To see the article click here.
Jin, J., Klasfeld, S., Zhu, Y., Fernandez Garcia, M., Xiao, J., Han, S.K., Konkol, A., Zhu, Y. & Wagner, D. (2021). LEAFY is a pioneer transcription factor and licenses cell reprogramming to floral fate. Nature Communications, 12(1), 626.
Master transcription factors reprogram cell fate in multicellular eukaryotes. Pioneer transcription factors have prominent roles in this process because of their ability to contact their cognate binding motifs in closed chromatin. Reprogramming is pervasive in plants, whose development is plastic and tuned by the environment, yet little is known about pioneer transcription factors in this kingdom. Here, we show that the master transcription factor LEAFY (LFY), which promotes floral fate through upregulation of the floral commitment factor APETALA1 (AP1), is a pioneer transcription factor. In vitro, LFY binds to the endogenous AP1 target locus DNA assembled into a nucleosome. In vivo, LFY associates with nucleosome occupied binding sites at the majority of its target loci, including AP1. Upon binding, LFY ‘unlocks’ chromatin locally by displacing the H1 linker histone and by recruiting SWI/SNF chromatin remodelers, but broad changes in chromatin accessibility occur later. Our study provides a mechanistic framework for patterning of inflorescence architecture and uncovers striking similarities between LFY and animal pioneer transcription factor.
Zhu, Y., Klasfeld, S., & Wagner, D. (2021). Molecular regulation of plant developmental transitions and plant architecture via PEPB family proteins–an update on mechanism of action. Journal of Experimental Botany, eraa598
This year marks the 100 th anniversary of the experiments by Garner and Allard (Garner and Allard, 1920) that showed that plants measure the duration of the night and day (the photoperiod) to time flowering. This discovery led to the identification of Flowering Locus T (FT) in Arabidopsis and Heading Date 3a (Hd3a) in rice as a mobile signal that promotes flowering in tissues distal to the site of cue perception. FT/Hd3a belong to the family of phosphatidylethanolamine binding proteins (PEBPs). Collectively, these proteins control plant developmental transitions and plant architecture. Several excellent recent reviews have focused on the roles of PEBP proteins in diverse plant species; here we will primarily highlight recent advances that enhance our understanding of the mechanism of action of PEBP proteins and discuss critical open questions.
In the mist of the USA elections, the Wagner Lab is over joyed to welcome Dr. Shalini Yadav. Dr. Yadav traveled all the way from the Indian Institute of Science Education and Research (IISER) in Mohali, India where she received her Ph.D. In the Wagner Lab she plans to study the role of antiflorigen Terminal Flower (TFL1) in axillary meristem fate.