An overview of pigment gland morphogenesis and its regulatory mechanism

Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait.

The interaction between epidermal growth factor (EGF) and matrix metalloproteinase induces the development of sweat glands in human fetal skin

Objective:The development of sweat glands is a very complicated biological process involving many factors. In this study, we explore the inter-relationship between epidermal growth factor (EGF), matrix metalloproteinases (MMP-2,MMP-7) and development of sweat glands in human embryos. Furthermore, we hope to elucidate the mechanism(s) underlying the induction of epidermal stem cells into sweat gland cells.

Single-cell transcriptomic analysis reveals the developmental trajectory and transcriptional regulatory networks of pigment glands in Gossypium bicki

Comprehensive utilization of cottonseeds is limited by the presence of pigment glands and its inclusion gossypol.The ideal cotton has glandless seeds but a glanded plant,a trait found in only a few Australian wild cotton species,including Gossypium bickii.Introgression of this trait into cultivated species has proved to be difficult.Understanding the biological processes toward pigment gland morphogenesis and the associated underlying molecular mechanisms will facilitate breeding of cultivated cotton varieties with the trait of glandless seeds and glanded plant.In this study,single-cell RNA sequencing(scRNA-seg)was performed on 12222 protoplasts isolated from cotyledons of germinating G.bicki seeds 48 h after imbibition.Clustered into 14 distinct clusters unsupervisedly,these cells could be grouped into eight cell populations with the assistance of known cell marker genes.The pigment gland cells were well separated from others and could be separated into pigment gland parenchyma cells,secretory cells,and apoptotic cells.By integrating the pigment gland cell developmental trajectory,transcription factor regulatory networks,and core transcription factor functional validation,we established a model for pigment gland formation.In this model,light and gibberellin were verified to promote the formation of pigment glands.In addition,three novel genes,GbiERF114(ETHYLENE RESPONSE FACTOR 114),GbiZAT11(ZINC FINGER OF ARABIDOPSIS THALIANA 11),and GbiNTL9(NAC TRANSCRIPTION FACTOR-LIKE 9),Were found to affect pigment gland formation.Collectively,these findings provide new insights into pigment gland morphogenesis and lay the cornerstone for future cotton scRNA-seq investigations.