Updates on molecular mechanisms in the development of branched trichome in Arabidopsis and nonbranched in cotton

Abstract

Summary Trichomes are specialized epidermal cells and a vital plant organ that protect plants from various harms and provide valuable resources for plant development and use. Some key genes related to trichomes have been identified in the model plant Arabidopsis thaliana through glabrous mutants and gene cloning, and the hub MYB ‐ bHLH ‐ WD 40, consisting of several factors including GLABRA 1 ( GL 1), GL 3, TRANSPARENT TESTA GLABRA 1 ( TTG 1), and ENHANCER OF GLABRA 3 ( EGL 3), has been established. Subsequently, some upstream transcription factors, phytohormones and epigenetic modification factors have also been studied in depth. In cotton, a very important fibre and oil crop globally, in addition to the key MYB ‐like factors, more important regulators and potential molecular mechanisms (e.g. epigenetic modifiers, distinct metabolic pathways) are being exploited during different fibre developmental stages. This occurs due to increased cotton research, resulting in the discovery of more complex regulation mechanisms from the allotetraploid genome of cotton. In addition, some conservative as well as specific mediators are involved in trichome development in other species. This study summarizes molecular mechanisms in trichome development and provides a detailed comparison of the similarities and differences between Arabidopsis and cotton, analyses the possible reasons for the discrepancy in identification of regulators, and raises future questions and foci for understanding trichome development in more detail.

Dissection of Dynamic Transcriptome Landscape of Leaf, Bract, and Lupulin Gland in Hop (Humulus lupulus L.)

“…The growing body of research suggested that phytohormones play significant roles in trichome initiation, development, and density regulation by mediating downstream genes [53]. Gibberellin and jasmonic acid exhibited a synergistic effect on trichome production, and the effect of these two phytohormones reflected an increased proportion of cells that developed into trichomes, despite an increase in the overall epidermal cell number of the leaves in Arabidopsis [54].…”

Comparative Mapping and Correlation Analysis Revealed Differentiation in the Genetic Basis of Stem Trichome Development Between Cultivated Tetraploid Cotton Species

“…Thus, Arabidopsis could serve as a model for elucidating the genetic mechanisms controlling cotton ber development [31][32]. Many genes were identi ed by homoeologous cloning and con rmed to be related to ber development [2]. There has been long-standing interest in whether the genetics of simply inherited traits, such as trichomes in cotton, could increase our understanding of more complex processes, such as lint ber development [31,33].…”

“…Their easy manipulation and observation made plant trichomes ideal for studying cell differentiationrelated pathways [2][3]. The trichomes of Arabidopsis thaliana have a specialized unicellular structure and are 200-500 µm in length.…”

“…Cotton ber is the most important raw material in the textile industry, and cotton seeds contain high oil and protein contents that are consumed by animals and humans [10]. Cotton bers are single-celled structures originating from the ovular epidermis, while trichomes originate from aerial epidermis [2,11], each by similar developmental processes [12]. Trichomes are broadly classi ed into glandular and nonglandular forms, and their morphology has been described in detail by Turley et al (2012).…”

Genome-wide analysis of CrRLK1L genes and their expression profiling during fiber development in cotton

“…Cotton is an important economic crop that provides ber for textile industry. Cotton ber is a single cell differentiated from the epidermal ovule, and its development consists of four overlapping stages including ber initiation, elongation, second cell wall biosynthesis and maturation [12], which are regulated by many genes [13]. For instance, GbMYB2 was speci cally expressed in the epidermal layer of ovule and bers, and overexpression of GbMYB2 in Arabidopsis displayed enhanced trichromes growth on leaves and longer roots [14].…”