scholarly journals Dual function of clock component OsLHY sets critical day length for photoperiodic flowering in rice

2021 ◽  
Author(s):  
Changhui Sun ◽  
Kuan Zhang ◽  
Yi Zhou ◽  
Lin Xiang ◽  
Changcai He ◽  
...  
Keyword(s):  
Day Length ◽  
Dual Function ◽  
Photoperiodic Flowering ◽  
Clock Component

scholarly journals FLOWERING HTH1 is involved in CONSTANS-mediated flowering regulation in Arabidopsis

2019 ◽  
Vol 62 (1) ◽  
Author(s):  
Soon Ae Sim ◽  
Su Gyeong Woo ◽  
Dae Yeon Hwang ◽  
Jin-Hong Kim ◽  
Seung Sik Lee ◽  
...  
Keyword(s):  
Subcellular Location ◽  
Day Length ◽  
Interacting Protein ◽  
Photoperiodic Flowering ◽  
Family Protein ◽  
Flowering Regulation ◽  
Delayed Flowering ◽  
The Right ◽  
Two Hybrid ◽  
Repression Domain

Abstract Flowering at the right time is essential for maximum reproductive fitness. In Arabidopsis thaliana, the CONSTANS (CO) protein facilitates the transition from the vegetative phase to the reproductive phase under long-day conditions. The formation of heterodimeric complexes between CO and DNA binding domain-containing transcription factors is important for the induction of day length-dependent flowering. Here, we report a myb-like helix turn helix (HTH) transcriptional regulator family protein as a new modulator of floral transition, which we have named FLOWERING HTH1 (FHTH1). We isolated FHTH1 as a CO-interacting protein by a yeast two-hybrid screen using an Arabidopsis transcription factor library. Our analysis showed that FHTH1 presented in the nucleus and the FHTH1-CO complex was formed in the same subcellular location. We also observed the expression of a FHTH1:GUS construct in the leaf vasculature, where CO exists. Transgenic plants overexpressing FHTH1 fused with the plant-specific repression domain SRDX showed a delayed flowering phenotype in long days, resembling the phenotype of the co mutant. Our results suggest that FHTH1 may contribute to CO-mediated photoperiodic flowering regulation.

scholarly journals Photoperiodic Flowering Response of Essential Oil, Grain, and Fiber Hemp (Cannabis sativa L.) Cultivars

2021 ◽  
Vol 12 ◽  
Author(s):  
Mengzi Zhang ◽  
Steven L. Anderson ◽  
Zachary T. Brym ◽  
Brian J. Pearson
Keyword(s):  
Essential Oil ◽  
Environmental Conditions ◽  
Cannabis Sativa ◽  
Day Length ◽  
Tropical Region ◽  
Floral Initiation ◽  
Flowering Response ◽  
Photoperiodic Flowering ◽  
Critical Photoperiod ◽  
Different Sources

Cultivation of hemp (Cannabis sativa L.) in tropical and subtropical regions can be challenging if the flowering behavior of a given cultivar is unknown, poorly understood, or not accurately selected for the photoperiod. Identifying cultivars adapted to local environmental conditions is key to optimizing hemp vegetative and flowering performance. We investigated the effects of varying light cycles in regulating extension growth and flowering response of 15 essential oil and 12 fiber/grain hemp cultivars both indoors and outdoors. Plants were subjected to 11 photoperiods in the controlled rooms ranging from 12 to 18 h, and natural day length in the field. The critical photoperiod threshold was identified for seven essential oil cultivars and two fiber/grain cultivars. “Cherry Wine-CC,” “PUMA-3,” and “PUMA-4” had the shortest critical day length between 13 h 45 min and 14 h. The flowering of essential oil cultivars was generally delayed by 1–2 days when the photoperiod exceeded 13 h compared with 12 h, and flowering was further delayed by 7–8 days when the photoperiod exceeded 14 h. In fiber/grain cultivars, flowering was generally delayed by 1–3 days when the day length exceeded 14 h. Flowering for most essential oil cultivars was delayed by 5–13 days under a 14-h photoperiod compared with 13 h 45 min, suggesting a photoperiod difference as little as 15 min can significantly influence the floral initiation of some essential oil cultivars. Cultivars represented by the same name but acquired from different sources can perform differently under the same environmental conditions, suggesting genetic variation among cultivars with the same name. Average days to flower of fiber/grain cultivars was correlated with reported cultivar origin, with faster flowering occurring among northern cultivars when compared with southern cultivars. Plant height generally increased as the day length increased in essential oil cultivars but was not affected in fiber/grain cultivars. In addition, civil twilight of ~2 μmol·m−2·s−1 was discovered to be biologically effective in regulating hemp flowering. Collectively, we conclude that most of the essential oil cultivars and some southern fiber/grain cultivars tested express suitable photoperiods for tropical and sub-tropical region cultivation.

scholarly journals Dual functions of ZmGI1 in the photoperiodic flowering pathway and salt stress responses in maize

2021 ◽  
Author(s):  
Fengkai Wu ◽  
Ling Liu ◽  
Yan Kang ◽  
Jing Li ◽  
Zhiyu Ma ◽  
...  
Keyword(s):  
Salt Stress ◽  
Flowering Time ◽  
Stress Responses ◽  
Redox Balance ◽  
Fine Tuning ◽  
Photoperiod Response ◽  
Rhythmic Pattern ◽  
Abiotic Stress Response ◽  
Photoperiodic Flowering ◽  
Clock Component

The circadian clock perceives photoperiodic changes and initiates processes leading to floral transition. GIGANTEA (GI) primarily functions as a principal clock component that integrates environmental cues into regulation of growth and development in Arabidopsis. However, it is unclear whether ZmGIs regulate photoperiodic flowering and abiotic stress response. Here, we demonstrated that the expression of ZmGI1 depicted a typical circadian pattern and was differentially expressed under LDs and SDs in photoperiodic sensitive and insensitive maize lines. The transcription level was significantly and positively correlated with days to silking and photoperiodic sensitivity in maize. Moreover, natural variation in ZmGI1 was associated with maize photoperiod response and the fine-tuning of plant development traits. Overexpression of ZmGI1Huangzao4 induced early flowering and enhanced salt tolerance in Arabidopsis relative to the wild-type and gi mutants. ZmGI1 formed a protein complex with ZmFKF1 and acted as a positive regulator of flowering time by regulating CONSTANS transcription in the photoperiod pathway. The ZmGI1/ZmThox complex regulates oxidative stress induced by salt stress via a redox balance pathway. Over all, we have provided compelling evidence to suggest that ZmGI1 is a pleotropic gene whose expression depicts a typical circadian rhythmic pattern and regulates flowering time and confers salt stress tolerance.

scholarly journals Flowering in time: genes controlling photoperiodic flowering in Arabidopsis

2001 ◽  
Vol 356 (1415) ◽  
pp. 1761-1767 ◽  
Author(s):  
Jo Putterill
Keyword(s):  
Arabidopsis Thaliana ◽  
Flowering Time ◽  
Recent Progress ◽  
Day Length ◽  
Sharp Transition ◽  
Photoperiodic Flowering ◽  
Expression Of Genes ◽  
Made In ◽  
Transition To Flowering

Successful sexual reproduction in plants relies upon the strict coordination of flowering time with favourable seasons of the year. One of the most important seasonal cues for the model plant Arabidopsis thaliana ( Arabidopsis ) is day length. Genes influencing flowering time in Arabidopsis have been isolated, some of which are involved in the perception and signalling of day length. This review discusses recent progress that has been made in understanding how Arabidopsis integrates environmental and internal signals to ensure a sharp transition to flowering and new insights on the role of the circadian clock in controlling the expression of genes that promote flowering in response to day length.

scholarly journals Molecular Characterization of Photoperiodic Flowering in Cultivated Strawberry

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1105D-1105
Author(s):  
Philip Stewart ◽  
Daniel Sargent ◽  
Thomas Davis ◽  
Kevin Folta
Keyword(s):  
Arabidopsis Thaliana ◽  
Molecular Characterization ◽  
Molecular Mechanisms ◽  
Expression Patterns ◽  
Model Systems ◽  
Day Length ◽  
Photoperiodic Flowering ◽  
Long Day ◽  
Flowering Control

The molecular mechanisms governing photoperiodic flowering has been well defined in the model systems of Arabidopsis thaliana(a facultative long-day plant) and rice (a short-day plant). Photoperiodic flowering control is of great interest to strawberry (Fragaria×ananassa) breeders and growers, and the genetics of photoperiodic flowering have been well studied, indicating that response to day-length is regulated by a small number of genetic loci. Cultivated strawberry is octoploid, so identification of these loci through forward genetic analyses is not practical. Since the componentry of the flowering response is generally conserved between monocots and dicots, we may assume that similar, if not identical, systems are functioning in strawberry as well. The goal of this work is to understand how cultivars likely containing identical photoperiod-sensing components are differentially sensitive to daylength. The expression patterns of genes relevant to the floraltransition were assessed under specific photoperiod conditions to assess similarities and/or differences to the model systems.

scholarly journals PRMT6 physically associates with nuclear factor Y to regulate photoperiodic flowering in Arabidopsis

aBIOTECH ◽  
2021 ◽  
Author(s):  
Pingxian Zhang ◽  
Xiulan Li ◽  
Yifan Wang ◽  
Weijun Guo ◽  
Sadaruddin Chachar ◽  
...  
Keyword(s):  
Flowering Time ◽  
Underlying Mechanism ◽  
Arginine Methylation ◽  
Day Length ◽  
Protein Arginine Methyltransferases ◽  
Nuclear Factor Y ◽  
Photoperiodic Flowering ◽  
Nuclear Factors ◽  
Positive Regulators ◽  
Flowering Locus

AbstractThe timing of floral transition is critical for reproductive success in flowering plants. In long-day (LD) plant Arabidopsis, the floral regulator gene FLOWERING LOCUS T (FT) is a major component of the mobile florigen. FT expression is rhythmically activated by CONSTANS (CO), and specifically accumulated at dusk of LDs. However, the underlying mechanism of adequate regulation of FT transcription in response to day-length cues to warrant flowering time still remains to be investigated. Here, we identify a homolog of human protein arginine methyltransferases 6 (HsPRMT6) in Arabidopsis, and confirm AtPRMT6 physically interacts with three positive regulators of flowering Nuclear Factors YC3 (NF-YC3), NF-YC9, and NF-YB3. Further investigations find that AtPRMT6 and its encoding protein accumulate at dusk of LDs. PRMT6-mediated H3R2me2a modification enhances the promotion of NF-YCs on FT transcription in response to inductive LD signals. Moreover, AtPRMT6 and its homologues proteins AtPRMT4a and AtPRMT4b coordinately inhibit the expression of FLOWERING LOCUS C, a suppressor of FT. Taken together, our study reveals the role of arginine methylation in photoperiodic pathway and how the PRMT6-mediating H3R2me2a system interacts with NF-CO module to dynamically control FT expression and facilitate flowering time.

scholarly journals Real-Time Monitoring of Key Gene Products Involved in Rice Photoperiodic Flowering

2021 ◽  
Vol 12 ◽  
Author(s):  
Hayato Yoshioka ◽  
Keiko Kimura ◽  
Yuko Ogo ◽  
Namie Ohtsuki ◽  
Ayako Nishizawa-Yokoi ◽  
...  
Keyword(s):  
Real Time ◽  
Gene Product ◽  
Monitoring System ◽  
Heading Date ◽  
Day Length ◽  
Gene Products ◽  
Real Time Monitoring ◽  
Photoperiodic Flowering ◽  
Long Day ◽  
Floral Repressor

Flowering is an important biological process through which plants determine the timing of reproduction. In rice, florigen mRNA is induced more strongly when the day length is shorter than the critical day length through recognition of 30-min differences in the photoperiod. Grain number, plant height, and heading date 7 (Ghd7), which encodes a CCT-domain protein unique to monocots, has been identified as a key floral repressor in rice, and Heading date 1 (Hd1), a rice ortholog of the Arabidopsis floral activator CONSTANS (CO), is another key floral regulator gene. The Hd1 gene product has been shown to interact with the Ghd7 gene product to form a strong floral repressor complex under long-day conditions. However, the mRNA dynamics of these genes cannot explain the day-length responses of their downstream genes. Thus, a real-time monitoring system of these key gene products is needed to elucidate the molecular mechanisms underlying accurate photoperiod recognition in rice. Here, we developed a monitoring system using luciferase (LUC) fusion protein lines derived from the Ghd7-LUC and Hd1-LUC genes. We successfully obtained a functionally complemented gene-targeted line for Ghd7-LUC. Using this system, we found that the Ghd7-LUC protein begins to accumulate rapidly after dawn and reaches its peak more rapidly under a short-day condition than under a long-day condition. Our system provides a powerful tool for revealing the accurate time-keeping regulation system incorporating these key gene products involved in rice photoperiodic flowering.

scholarly journals Photoperiodic Flowering Response of Essential Oil, Grain, and Fiber Hemp (Cannabis sativa L.) Cultivars

2021 ◽  
Author(s):  
Mengzi Zhange ◽  
Steven L Anderson ◽  
Zachary Brym ◽  
Brian J. Pearson
Keyword(s):  
Essential Oil ◽  
Environmental Conditions ◽  
Cannabis Sativa ◽  
Day Length ◽  
Tropical Region ◽  
Floral Initiation ◽  
Flowering Response ◽  
Photoperiodic Flowering ◽  
Critical Photoperiod ◽  
Different Sources

Cultivation of hemp (Cannabis sativa L.) in tropical and subtropical regions can be challenging if flowering behavior of a given cultivar is unknown, poorly understood, or not accurately selected for the photoperiod. Identifying cultivars adapted to local environmental conditions is key to optimizing hemp vegetative and flowering performance. We investigated the effects of varying light cycles in regulating extension growth and flowering response of 15 essential oil and 12 fiber/grain hemp cultivars both in indoors and outdoors. Plants were subjected to eleven photoperiods in the controlled rooms ranging from 12 h to 18 h, and natural day length in the field. The critical photoperiod threshold was identified for seven essential oil cultivars and two fiber/grain cultivars. 'Cherry Wine-CC', 'PUMA-3', and 'PUMA-4' had the shortest critical day length between 13 h 45 min and 14 h. The flowering of essential oil cultivars was generally delayed by 1 to 2 d when photoperiod exceeded 13 h compared to 12 h, and flowering was further delayed by 7 to 8 d when photoperiod exceed 14 h. In fiber/grain cultivars, flowering was generally delayed by 1 to 3 d when day length exceeded 14 h. Flowering for most essential oil cultivars was delayed by 5 to 13 d under 14 h photoperiod compared to 13 h 45 min, suggesting a photoperiod difference as little as 15 min can significantly influence the floral initiation of some essential oil cultivars. Cultivars represented by the same name but acquired from different sources can perform differently under the same environmental conditions, suggesting genetic variation among cultivars with the same name. Average days to flower of fiber/grain cultivars was correlated with reported cultivar origin with faster flowering occurring among northern cultivars when compared to southern cultivars. Plant height generally increased as the day length increased in essential oil cultivars but was not affected in fiber/grain cultivars. In addition, civil twilight of approximately 2 μmol m^-2 s^-1 was discovered to be biologically effective in regulating hemp flowering. Collectively, we conclude that most of the essential oil cultivars and some southern fiber/grain cultivars tested express suitable photoperiods for tropical and sub-tropical region cultivation.

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