Seasonal cycles of environmental cues generate variation in the timing of life-history transition events across taxa. It is through the entrainment of internal, endogenous rhythms of organisms to these external, exogenous rhythms in environment, such as cycling temperature and daylight, by which organisms can regulate and time life history transitions. Here, we review the current understanding of how photoperiod both stimulates and terminates seasonal reproduction in birds. The review describes the role of external coincidence timing, the process by which photoperiod is proposed to stimulate reproductive development. Then, the molecular basis of light detection and the photoperiodic regulation of neuroendocrine timing of seasonal reproduction in birds is presented. Current data indicates that vertebrate ancient opsin is the predominant photoreceptor for light detection by the hypothalamus, compared to neuropsin and rhodopsin. The review then connects light detection to well-characterized hypothalamic and pituitary gland molecules involved in the photoperiodic regulation of reproduction. In birds, Gonadotropin-releasing hormone synthesis and release are controlled by photoperiodic cues via thyrotropin-stimulating hormone-β (TSHβ) independent and dependent pathways, respectively. The review then highlights the role of D-box and E-box binding motifs in the promoter regions of photoperiodic genes, in particular Eyes-absent 3, as the key link between circadian clock function and photoperiodic time measurement. Based on the available evidence, the review proposes that at least two molecular programs form the basis for external coincidence timing in birds: photoperiodic responsiveness by TSHβ pathways and endogenous internal timing by gonadotropin synthesis.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/jez.2604 | DOI Listing |
Plant Cell Rep
December 2024
School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, Xinxiang, 453003, China.
BrSWEET11 accelerated Arabidopsis thaliana flowering, while silencing Brsweet11 in Brassica rapa delayed flowering relative to controls. BrSWEET11 is involved in sucrose transport after being induced by long-day conditions. SWEETs (Sugars Will Eventually Be Exported Transporters) are sugar outflow transporters that may participate in the regulation of plant flowering.
View Article and Find Full Text PDFBMC Plant Biol
December 2024
College of Life Sciences, Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, Changchun, 130118, China.
Background: Safflower thrives in dry environments but faces difficulties with flowering in wet and rainy summers. Flavonoids play a role in flower development and can potentially alleviate these challenges. Furthermore, the FLOWERING LOCUS T (FT) family of phosphatidylethanolamine-binding protein (PEBP) genes play a crucial role in the photoperiodic flowering pathway.
View Article and Find Full Text PDFPlant Cell Environ
December 2024
ICAR-National Institute for Plant Biotechnology, New Delhi, India.
The present study investigated the linkage between days to flowering (DTF) and growth habit (GH) in pigeonpea using QTL mapping, QTL-seq, and GWAS approaches. The linkage map developed here is the largest to date, spanning 1825.56 cM with 7987 SNP markers.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
November 2024
School of Pharmacy, Henan University of Chinese Medicine Zhengzhou 450046, China Henan Key Laboratory of Chinese Medicine Resources and Chemistry Zhengzhou 450046, China Collaborative Innovation Center of Research and Development on the Whole Industry Chain of Yu-Yao Zhengzhou 450046, China.
Trihelix transcription factors play important roles in plant light responses, growth and development, and stress responses. However, Trihelix has not yet been reported in Eucommia ulmoides. In this study, bioinformatics methods were used to comprehensively identify and analyze the expression patterns of the Trihelix gene family in E.
View Article and Find Full Text PDFJ Photochem Photobiol B
December 2024
Department of Zoology, University of Lucknow, Lucknow, Uttar Pradesh 226007, India. Electronic address:
Animals use photic cues to time their daily and seasonal activity. The role of photoperiod has been much investigated in seasonal responses, but the role of light intensity is less understood in passerine finches. We investigated if and how daytime light intensity influences photoinduced migratory phenologies and hypothalamic mRNA expressions in a Palearctic-Indian migratory finch, redheaded bunting (Emberiza bruniceps).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!