A Synthetic Cytokinin Improves Photosynthesis in Rice under Drought Stress by Modulating the Abundance of Proteins Related to Stomatal Conductance, Chlorophyll Contents, and Rubisco Activity
PLANTS-BASEL
Authors: Gujjar, Ranjit Singh; Banyen, Pennapa; Chuekong, Wannisa; Worakan, Phapawee; Roytrakul, Sittiruk; Supaibulwatana, Kanyaratt
Abstract
Drought susceptible rice cultivar PTT1 (Pathumthani1) was treated with drought (-72 kPa) and CPPU (N-2-(chloro-4-pyridyl)-N-phenyl urea) @ 5 mg/L at tillering and grain-filling stages. Plants were tested for the effect of synthetic cytokinin on the parameters influencing the process of photosynthesis. Exogenous spray of CPPU improved the stomatal conductance of rice leaves, which was severely reduced by drought. The abundance intensities of proteins, associated with the stomatal conductance (ZEP, NCED4, PYL9, PYL10, ABI5, SnRK4, Phot1, and Phot2), were also in agreement with the positive impact of CPPU on the stomatal conductance under drought stress. Among the photosynthetic pigments, Chl b contents were significantly reduced by drought stress, whereas CPPU treated plants retained the normal contents of Chl b under drought stress. Subsequently, we examined the abundance intensities of chlorophyll synthase and HCR proteins, implicated in the biosynthesis of chlorophyll pigments and the conversion of Chl b to Chl a, respectively. The results indicated a drought-mediated suppression of chlorophyll synthase. However, CPPU treated plants retained normal levels of chlorophyll synthase under drought stress. In addition, drought stress induced HCR proteins, which might be the cause for reduced Chl b contents in drought stressed plants. Further, CPPU treatment helped the plants sustain photosynthesis at a normal rate under drought stress, which was comparable with well-watered plants. The results were further confirmed by examining the abundance intensities of two key proteins, RAF1 and Rubisco activase, implicated in the assembly and activation of Rubisco, respectively. CPPU treatment reversed the drought mediated suppression of these proteins at both of the growth stages of rice under drought stress. Based on the results, it can be suggested that synthetic cytokinins help the plants sustain photosynthesis at a normal rate under drought stress by positively influencing the determinants of photosynthesis at a molecular level.
Integrative Clinical Genomics of Advanced Prostate Cancer
CELL
Authors: Robinson, Dan; Van Allen, Eliezer M.; Wu, Yi-Mi; Schultz, Nikolaus; Lonigro, Robert J.; Mosquera, Juan-Miguel; Montgomery, Bruce; Taplin, Mary-Ellen; Pritchard, Colin C.; Attard, Gerhardt; Beltran, Himisha; Abida, Wassim; Bradley, Robert K.; Vinson, Jake; Cao, Xuhong; Vats, Pankaj; Kunju, Lakshmi P.; Hussain, Maha; Feng, Felix Y.; Tomlins, Scott A.; Cooney, Kathleen A.; Smith, David C.; Brennan, Christine; Siddiqui, Javed; Mehra, Rohit; Chen, Yu; Rathkopf, Dana E.; Morris, Michael J.; Solomon, Stephen B.; Durack, Jeremy C.; Reuter, Victor E.; Gopalan, Anuradha; Gao, Jianjiong; Loda, Massimo; Lis, Rosina T.; Bowden, Michaela; Balk, Stephen P.; Gaviola, Glenn; Sougnez, Carrie; Gupta, Manaswi; Yu, Evan Y.; Mostaghel, Elahe A.; Cheng, Heather H.; Mulcahy, Hyojeong; True, Lawrence D.; Plymate, Stephen R.; Dvinge, Heidi; Ferraldeschi, Roberta; Flohr, Penny; Miranda, Susana; Zafeiriou, Zafeiris; Tunariu, Nina; Mateo, Joaquin; Perez-Lopez, Raquel; Demichelis, Francesca; Robinson, Brian D.; Schiffman, Marc; Nanus, David M.; Tagawa, Scott T.; Sigaras, Alexandros; Eng, Kenneth W.; Elemento, Olivier; Sboner, Andrea; Heath, Elisabeth I.; Scher, Howard I.; Pienta, Kenneth J.; Kantoff, Philip; de Bono, Johann S.; Rubin, Mark A.; Nelson, Peter S.; Garraway, Levi A.; Sawyers, Charles L.; Chinnaiyan, Arul M.
Abstract
Toward development of a precision medicine framework for metastatic, castration-resistant prostate cancer (mCRPC), we established a multi-institutional clinical sequencing infrastructure to conduct prospective whole-exome and transcriptome sequencing of bone or soft tissue tumor biopsies from a cohort of 150 mCRPC affected individuals. Aberrations of AR, ETS genes, TP53, and PTEN were frequent (40%-60% of cases), with TP53 and AR alterations enriched in mCRPC compared to primary prostate cancer. We identified new genomic alterations in PIK3CA/B, R-spondin, BRAF/RAF1, APC, beta-catenin, and ZBTB16/PLZF. Moreover, aberrations of BRCA2, BRCA1, and ATM were observed at substantially higher frequencies (19.3% overall) compared to those in primary prostate cancers. 89% of affected individuals harbored a clinically actionable aberration, including 62.7% with aberrations in AR, 65% in other cancer-related genes, and 8% with actionable pathogenic germline alterations. This cohort study provides clinically actionable information that could impact treatment decisions for these affected individuals.