Comparative Transcriptome Analysis of Gene Expression and Regulatory Characteristics Associated with Different Bolting Periods in Spinacia oleracea

Abstract

Bolting is a symbol of the transition from vegetative to reproductive growth in plants. Late bolting can effectively prolong the commercial value of spinach and is of great importance for spinach breeding. Bolting has complex regulatory networks, and current research on spinach bolting is relatively weak, with specific regulatory pathways and genes unclear. To clarify the regulatory characteristics and key genes related to bolting in spinach, we conducted a comparative transcriptome analysis. In this study, 18 samples from three periods of bolting-tolerant spinach material 12S3 and bolting-susceptible material 12S4 were analyzed using RNA-seq on, resulting in 10,693 differentially expressed genes (DEGs). Functional enrichment and co-expression trend analysis indicated that most DEGs were enriched in the photoperiod pathway, the hormone signaling pathway, and the cutin, suberin, and wax biosynthetic pathways. According to the weighted gene co-expression network analysis (WGCNA), SpFT (SOV4g003400), SOV4g040250, and SpGASA1 (SOV6g017600) were likely to regulate bolting through the gibberellin and photoperiod pathways, and SpELF4 (SOV1g028600) and SpPAT1 (SOV4g058860) caused differences in early and late bolting among different cultivars. These results provide important insights into the genetic control of bolting in spinach and will help elucidate the molecular mechanisms of bolting in leafy vegetables.