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Genomic Expansion and Subgenome Expression Divergence of Sugar Transporters During Polyploid Evolution of Bamboos
by
, and
Binao Zhou
1,2,3,4
,
Mingzhen Lv
1,2,3,5,
Weixin Yan
1,2,3,5,
Xinyi Luo
1,2,3,5,
Wenjing Yao
1,2,3,4,5
and
Shuyan Lin
1,2,3,4,5,* 1
State Key Laboratory for Development and Utilization of Forest Food Resources, Nanjing Forestry University, Nanjing 210037, China
2
Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China
3
Bamboo Research Institute, Nanjing Forestry University, Nanjing 210037, China
4
College of Life Sciences, Nanjing Forestry University, Nanjing 210037, China
5
College of Forestry and Grassland, Nanjing Forestry University, Nanjing 210037, China
*
Author to whom correspondence should be addressed.
Biology 2026, 15(18), 1614; https://doi.org/10.3390/biology15181614 (registering DOI)
Submission received: 10 August 2026
/
Revised: 4 September 2026
/
Accepted: 11 September 2026
/
Published: 13 September 2026
Simple Summary
Bamboos include both herbaceous and woody species. Woody bamboos can grow remarkably fast, sometimes more than one meter per day, which requires a very efficient system to transport sugars from leaves to growing stems. In this study, we compared the genes that encode sugar transport proteins in 14 bamboo species. We found that woody bamboos have more copies of these sugar transport genes than herbaceous bamboos. The extra copies are not simply redundant; many of them show tissue-specific expression and are active at different stages of stem growth. This more specialized expression pattern may help woody bamboos deliver sugars more effectively to rapidly growing parts, supporting their explosive growth. Our findings provide new insights into how bamboo growth is regulated at the genetic level and may offer useful gene resources for improving sugar transport and yield in crops.
Abstract
Sugar transporters play a pivotal role in photoassimilate partitioning and biomass accumulation in plants. However, how whole-genome duplication (WGD) has reshaped the evolutionary trajectory of the sugar transport system in Bambusoideae remains elusive. Here, we systematically identified and characterized the SUT (Sucrose Transporters) and MST (Monosaccharide Transporters) gene families across 14 bamboo genomes representing four major lineages: herbaceous, temperate woody, neotropical woody and paleotropical woody bamboos. Our results suggest that WGD acted as the primary driving force behind the expansion of these gene families, with woody bamboos possessing significantly higher gene counts than herbaceous bamboos. Notably, extensive gene loss was observed in hexaploid lineages, aligning with the gene dosage balance hypothesis. Phylogenetic and sequence analyses demonstrated that core genes were subjected to purifying selection. Intriguingly, 21 groups of identical protein sequences across species were identified in paleotropical woody bamboos, suggesting high sequence conservation. Transcriptomic and syntenic analyses further unveiled the mechanisms of post-polyploidization expression divergence: homeologs exhibited marked expression asymmetry across subgenomes. Distinct from the broad expression pattern in herbaceous bamboos, which rely on SUT5 and a few STP (Sugar Transporter Protein) genes, woody bamboos have achieved fine-tuned expression partitioning and tissue-specific specialization during different culm developmental stages through significantly expanded SUT and STP family members. This study reveals an evolutionary pattern characterized by “WGD-driven expansion, post-polyploid fractionation, and subgenome expression divergence.” This pattern suggests a potential link to the enhanced sugar allocation efficiency required for the explosive growth of woody bamboos, offering valuable gene resources and a foundation for future functional studies in Poaceae crops.
