| Nucleotide sugar transporters (NSTs) participate in cell wall formation and anther development by transporting substrates into the Golgi apparatus, but the URGT (UDP-rhamnose/UDP-galactose transporter) subfamily in cotton has not been systematically characterized. In this study, a total of 39 URGT genes were identified in Gossypium arboreum, G. raimondii, G. hirsutum and G. barbadense using bioinformatics analysis. We further analyzed their gene characteristics, chromosomal localization, phylogeny, collinearity, cis-acting elements, gene structure, conserved motifs, transcriptome data, and expression patterns during different anther developmental stages. The results showed that URGT genes in cotton could be divided into three subgroups. Gene structure and conserved motif analyses revealed that they were relatively conserved during evolution. Segmental duplication was the main driving force for the expansion of this gene family. Ka/Ks analysis indicated that the evolution of URGT genes was mainly governed by purifying selection. Promoter cis-element analysis revealed that they were abundant in ABA/JA hormone-responsive elements and MYB transcription factor binding sites. Transcriptome analysis showed that the expression of URGT genes varied significantly across different tissues in G. hirsutum. Among them, GhURGT1-6 and GhURGT1-11 exhibited specifically high expression in stamens. Transcriptome and qRT-PCR analyses at different anther developmental stages further revealed that these two genes were highly expressed at the meiosis stage and pollen maturation stage. These results lay a foundation for further functional research of the URGT family during cotton anther development. |