NUCLEAR FACTOR Y, Subunit C (NF-YC) Transcription Factors Are Positive Regulators of Photomorphogenesis in Arabidopsis thaliana

PLoS Genet. 2016 Sep 29;12(9):e1006333. doi: 10.1371/journal.pgen.1006333. eCollection 2016 Sep.

Abstract

Recent reports suggest that NF-Y transcription factors are positive regulators of skotomorphogenesis in Arabidopsis thaliana. Three NF-YC genes (NF-YC3, NF-YC4, and NF-YC9) are known to have overlapping functions in photoperiod dependent flowering and previous studies demonstrated that they interact with basic leucine zipper (bZIP) transcription factors. This included ELONGATED HYPOCOTYL 5 (HY5), which has well-demonstrated roles in photomorphogenesis. Similar to hy5 mutants, we report that nf-yc3 nf-yc4 nf-yc9 triple mutants failed to inhibit hypocotyl elongation in all tested light wavelengths. Surprisingly, nf-yc3 nf-yc4 nf-yc9 hy5 mutants had synergistic defects in light perception, suggesting that NF-Ys represent a parallel light signaling pathway. As with other photomorphogenic transcription factors, nf-yc3 nf-yc4 nf-yc9 triple mutants also partially suppressed the short hypocotyl and dwarf rosette phenotypes of CONSTITUTIVE PHOTOMORPHOGENIC 1 (cop1) mutants. Thus, our data strongly suggest that NF-Y transcription factors have important roles as positive regulators of photomorphogenesis, and in conjunction with other recent reports, implies that the NF-Y are multifaceted regulators of early seedling development.

Grants and funding

The research described here was funded by the National Science Foundation (IOS 1149822 award to BFH, www.nsf.gov) and the University of Oklahoma Research Council (https://vpr-norman.ou.edu/research-council). National Science Foundation and the University of Oklahoma had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.