关键词: 端粒, 端粒酶, 端粒结合蛋白, 植物衰老

Abstract:

The investigation of plant senescence and seed deterioration mechanisms has emerged as a prominent and highly significant subject in the field of agricultural science. Plant senescence can exert a profound negative impact on agriculture， while premature senescence of forage grasses can engender diminished grassland productivity and impede the progress of the grass industry. Additionally， seed deterioration leads to an annual loss of viability in approximately 25% of global seeds， resulting in substantial economic losses and significantly hampering the healthy advancement of agriculture. Gaining a comprehensive and profound understanding of plant senescence characteristics and regulatory mechanisms offers immense value not only in unraveling plant ecological adaptations and population stability but also in offering vital practical implications for the selection of senescence retardation techniques and regulatory measures. In the model plant Arabidopsis thaliana， extensive evidence indicates a close and intricate interrelation among chromosomal telomeres， plant senescence， and seed viability. Telomeres， repetitive DNA sequences situated at the chromosomal termini， encompass telomeric DNA and associated binding proteins. Telomere-binding proteins form a pivotal protein ensemble that primarily assumes the role of stabilizing telomere structure and safeguarding telomeres against disturbances originating from the DNA repair system. Moreover， these proteins actively partake in numerous fundamental biological processes， including gene expression， DNA replication， and the modulation of chromosomal architecture. Telomerase， comprising two subunits-telomerase reverse transcriptase （TERT） and telomerase RNA （TER）-exerts its influence on mitochondrial function and the regulation of pertinent gene expression. By exploring the nascent functionalities of telomerase， we can facilitate advances in plant stress resistance， subsequently postponing the onset of plant senescence and creating novel pathways towards enhanced crop yield. Recent investigations conducted on plants have unveiled a compelling correlation between telomere dynamics and plant senescence， yet numerous question remain surrounding the precise mechanisms governing telomere homeostasis in plants. In the light of these findings， this study undertakes a comprehensive review of the roles fulfilled by telomeres and telomere-binding proteins in plant biology， with particular emphasis on the regulatory mechanisms governing telomere length and telomerase activity orchestrated by these pivotal elements. This work serves as a theoretical cornerstone， furnishing a vital reference for subsequent exploration of the intricacies of plant senescence and seed deterioration mechanisms.

Key words: telomere, telomerase, telomeric binding protein, plant senescence