SWEET Genes Regulate Development and Stress Responses in Cunninghamia lanceolata

A genome-wide survey of Cunninghamia lanceolata, a major fast-growing timber species in China, has identified 31 ClSWEET genes grouped into four clades. The study provides the first comprehensive catalog of SWEET genes in this species, addressing a sugar transporter family that remains largely unexplored in gymnosperms.

Conserved domain and motif analyses revealed strong intra-clade conservation among the identified genes. All ClSWEET genes carried at least one MtN3_slv domain, most contained two, and one uniquely possessed a third. In addition, the expansion of this gene family in Cunninghamia lanceolata was predominantly associated with segmental duplication.

Promoter profiling showed enrichment of cis-acting elements responsive to abscisic acid (ABA), methyl jasmonate (MeJA), jasmonic acid (JA), drought, and low temperature. These promoter characteristics implicate the ClSWEET family in hormonal and stress regulation.

Transcriptome analyses linked these genomic features to functional activity during somatic embryogenesis. Expression profiles showed that CULA01G01040.1 peaked at the mid-stage on day 15, whereas CULA02G72230.1 remained constitutively high throughout the developmental process.

Under environmental stress conditions, eight ClSWEET genes were differentially expressed under heat stress, with expression patterns confirmed by qRT-PCR validation. Furthermore, CULA01G01040.1 was strongly upregulated in stems under drought, cold stress, and anthracnose infection, whereas CULA04G40820.1 and CULA07G53650.1 were specifically induced in roots under cold stress, indicating dynamic and context-dependent roles in stress responses.

Subject of Research: SWEET gene family characterization and expression in Cunninghamia lanceolata

Article Title: Genome-wide identification and expression profiling of the SWEET gene family reveals its roles in somatic embryogenesis and stress responses in Cunninghamia lanceolata

Article References: Zhao, Q., Liu, Y., Zhu, L., Hao, Z., Zheng, R., Chen, Y., Lu, L., & Cheng, T. (2026). Genome-wide identification and expression profiling of the SWEET gene family reveals its roles in somatic embryogenesis and stress responses in Cunninghamia lanceolata. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09974-w

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09974-w

Keywords: Cunninghamia lanceolata, SWEET gene family, somatic embryogenesis, stress responses, gene expression, segmental duplication, plant biology, MtN3_slv domain, Genome-wide, identification, expression, profiling