The DMP (DOMAIN OF UNKNOWN FUNCTION 679 membrane protein) domain, containing a family of membrane proteins specific to green plants, is involved in numerous biological functions including physiological processes, reproductive development and senescence in Arabidopsis, but their evolutionary relationship and biological function in most crops remains unknown. In this study, we scrutinized phylogenetic relationships, gene structure, conserved domains and motifs, promoter regions, gene loss/duplication events and expression patterns. Overall, 240 DMPs were identified and analyzed in 24 plant species selected from lower plants to angiosperms. Comprehensive evolutionary analysis revealed that these DMPs underwent purifying selection and could be divided into five groups (I–V). DMP gene structure showed that it may have undergone an intron loss event during evolution. The five DMP groups had the same domains, which were distinct from each other in terms of the number of DMPs; group III was the largest, closely followed by group V. The DMP promotor region with various cis-regulatory elements was predicted to have a potential role in development, hormone induction and abiotic stresses. Based on transcriptomic data, expression profiling revealed that DMPs were primarily expressed in reproductive organs and were moderately expressed in other tissues. Evolutionary analysis suggested that gene loss events occurred more frequently than gene duplication events among all groups. Overall, this genome-wide study elucidates the potential function of the DMP gene family in selected plant species, but further research is needed in many crops to validate their biological roles.

Cotton (Gossypium hirsutum) is globally cultivated for its high-quality fiber; yet, its seed, rich in oil and protein, offers untapped potential for various applications, including food, feed, and industry. With cottonseed oil gaining renewed attention as a valuable co-product, efforts to enhance oil content must contend with long-standing breeding priorities focused on lint yield and fiber quality. A central challenge lies in the complex and often antagonistic genetic relationships between oil accumulation and key agronomic traits. Notably, negative correlations between seed oil content and fiber yield, as well as the pleiotropic nature of several regulatory genes and Quantitative Trait Loci (QTLs), present significant barriers to dual-trait improvement. This review synthesizes current knowledge on the genetic and molecular interplay between cottonseed oil content and other agronomic traits. We examine the architecture of oil-related QTLs and pleiotropic loci, co-expression patterns of shared transcriptional regulators, and metabolic trade-offs influencing carbon allocation between seed and fiber. Recent advances in genomics, transcriptomics, and systems biology are explored as tools to disentangle these trait interactions. We highlight strategies such as multi-trait genomic selection, CRISPR-based uncoupling of antagonistic loci, and the use of wild and exotic germplasm to overcome linkage drag. By providing an integrative overview of the constraints and opportunities at the intersection of oil and agronomic trait improvement, this review lays the groundwork for the development of dual-purpose cotton ideotypes. We propose a conceptual framework for breeding programs to simultaneously enhance fiber yield and oil productivity in a sustainable and climate-resilient manner.

Cotton (Gossypium hirsutum) is globally cultivated for its high-quality fiber; yet, its seed, rich in oil and protein, offers untapped potential to support various applications, including food, feed, and industry. With cottonseed oil gaining renewed attention as a valuable co-product, efforts to enhance oil content must contend with longstanding breeding priorities focused on lint yield and fiber quality. A central challenge lies in the complex and often antagonistic genetic relationships between oil accumulation and key agronomic traits. Notably, negative correlations between seed oil content and fiber yield, as well as the pleiotropic nature of several regulatory genes and Quantitative Trait Loci (QTLs), present significant barriers to dual-trait improvement. This review synthesizes current knowledge on the genetic and molecular interplay between cottonseed oil content and other agronomic traits. We examine the architecture of oil-related QTLs and pleiotropic loci, co-expression patterns of shared transcriptional regulators, and metabolic trade-offs influencing carbon allocation between seed and fiber. Recent advances in genomics, transcriptomics, and systems biology are explored as tools to disentangle these trait interactions. We highlight strategies such as multi-trait genomic selection, CRISPR-based uncoupling of antagonistic loci, and the use of wild and exotic germplasm to overcome linkage drag. By providing an integrative overview of the constraints and opportunities at the intersection of oil and agronomic trait improvement, this review lays the groundwork for the development of dual-purpose cotton ideotypes. We propose a conceptual framework for breeding programs to simultaneously enhance fiber yield and oil productivity in a sustainable and climate-resilient manner.

The membrane-bound proteins belonging to DUF677 (domain of unknown function 677) are found mainly in green plants. The function of the DUF677 gene (AT14A)