사과 및 배 MADS-box 유전자의 비교 유전체 분석 및 저온 스트레스 반응 특성 규명

MADS-box genes encode transcription factors critical for plant development, flowering, and stress responses. We re-annotated MADS-box genes in apple (Malus domestica) and pear (Pyrus pyrifolia), two economically significant Rosaceae species, revealing 113 previously unannotated genes. Comparative genomic analyses with Arabidopsis and other species highlighted evolutionary divergence, with domain and motif analyses demonstrating stronger conservation in MIKC-type genes compared to the M type. Phylogenetic reconstruction traced lineage-specific expansions, while a CAFE analysis identified SOC1 as the most rapidly expanding subfamily in Pyrus pyrifolia, likely driven by whole-genome duplication events—a pattern consistent with recent synteny network studies in Rosaceae. Under cold stress, expression profiling in Pyrus pyrifolia revealed a significant downregulation of SOC1, suggesting its role in temperature-sensitive signaling pathways. A co-expression network analysis further implicated PPYR_MADS_102 and PPYR_MADS_56 as key candidates for cold resistance, potentially regulating dormancy or stress-responsive pathways. Our study provides a refined genomic resource for Rosaceae, elucidates the evolutionary dynamics of MADS-box subfamilies, and identifies functional targets for improving cold tolerance in horticultural species.