A Lin28 homologue reprograms differentiated cells to stem cells in the moss Physcomitrella patens

Chen Li,Yuji Hiwatashi,Mitsuyasu Hasebe,Akihiro Imai,Yosuke Tamada,Minoru Kubo,Takashi Murata,Philip N Benfey,Yoshikatsu Sato,Yusuke Sako,Kari Thompson,Yukiko Kabeya,Dale Karlson,Masaki Ishikawa,Tomoaki Nishiyama,Shu-Hsing Wu

doi:10.1038/ncomms14242

Abstract

Both land plants and metazoa have the capacity to reprogram differentiated cells to stem cells. Here we show that the moss Physcomitrella patens Cold-Shock Domain Protein 1 (PpCSP1) regulates reprogramming of differentiated leaf cells to chloronema apical stem cells and shares conserved domains with the induced pluripotent stem cell factor Lin28 in mammals. PpCSP1 accumulates in the reprogramming cells and is maintained throughout the reprogramming process and in the resultant stem cells. Expression of PpCSP1 is negatively regulated by its 3′-untranslated region (3′-UTR). Removal of the 3′-UTR stabilizes PpCSP1 transcripts, results in accumulation of PpCSP1 protein and enhances reprogramming. A quadruple deletion mutant of PpCSP1 and three closely related PpCSP genes exhibits attenuated reprogramming indicating that the PpCSP genes function redundantly in cellular reprogramming. Taken together, these data demonstrate a positive role of PpCSP1 in reprogramming, which is similar to the function of mammalian Lin28.

Highlights

Both land plants and metazoa have the capacity to reprogram differentiated cells to stem cells
Cold-shock domain proteins (CSPs) were first identified in bacteria as proteins expressed under cold-shock conditions[15], and were later implicated in the process of cold acclimation in flowering plants as CSP transcripts accumulate after cold treatment in Arabidopsis and wheat[16,17,18]
As the Physcomitrella patens Cold-Shock Domain Protein 1 (PpCSP1) transcript level is B10-fold higher in the nPpCSP1-Citrine-nopaline synthase polyadenylation signal (nosT) line, we found that this transcript increase results in protruding non-edge cells (Fig. 4a–c)

Summary

Introduction

Both land plants and metazoa have the capacity to reprogram differentiated cells to stem cells. PpCSP1 accumulates in the reprogramming cells and is maintained throughout the reprogramming process and in the resultant stem cells. A quadruple deletion mutant of PpCSP1 and three closely related PpCSP genes exhibits attenuated reprogramming indicating that the PpCSP genes function redundantly in cellular reprogramming. Taken together, these data demonstrate a positive role of PpCSP1 in reprogramming, which is similar to the function of mammalian Lin[28]. On the other hand, differentiated cells can change their cell fate to stem cells under certain conditions in both land plants and metazoa[3,4]. With the addition of the appropriate phytohormones they can regenerate shoot and root meristems including stem cells, as was first shown with carrot in 1958

Methods

Results

Conclusion