Sugar Transporter Proteins (STPs) in Gramineae Crops: Comparative Analysis, Phylogeny, Evolution, and Expression...

Area of Science:

• Plant Biology
• Genomics
• Evolutionary Biology

Background:

• Sugar transporter proteins (STPs) are crucial for plant sugar transport, growth, and development.
• STPs have potential to enhance crop yield and stress tolerance, but their evolution in Gramineae crops is poorly understood.
• Functional differentiation of rice STPs also requires further investigation.

Purpose of the Study:

• To conduct a comparative genomic analysis of the STP gene family across seven representative Gramineae crops.
• To investigate the evolutionary dynamics, expansion mechanisms, and selective forces acting on STPs in these crops.
• To explore the functional roles of rice STPs, particularly in development and stress responses.

Main Methods:

• Comparative genomics of STP genes in *Brachypodium distachyon*, *Hordeum vulgare*, *Setaria italica*, *Sorghum bicolor*, *Zea mays*, *Oryza rufipogon*, and *Oryza sativa*.
• Identification and phylogenetic analysis of 177 STP genes, grouped into four clades.
• Analysis of gene duplication events, divergence times, selective pressures, and expression patterns.

Main Results:

• A total of 177 STP genes were identified and classified into four clades, with Clades I, III, and IV showing significant expansion.
• Tandem and whole-genome duplication events were key drivers of STP gene family expansion in most Gramineae crops.
• STP genes in Gramineae crops are under purifying selection, with variations across clades and orthologous groups. Rice STPs are involved in floral development and responses to abiotic stresses, infection, and wounding.

Conclusions:

• The study elucidates the expansion and evolutionary patterns of the STP gene family in Gramineae genomes.
• Different expansion mechanisms contribute to STP diversity across species.
• Findings provide insights for future functional studies of STPs to improve crop agronomic traits.