Spatial Expression and Functional Analysis of Casparian Strip Regulatory Genes in Endodermis Reveals the Conserved Mechanism in Tomato

Abstract

Casparian strip (CS) is an impregnation of endodermal cell wall, forming an apoplastic diffusion barrier which forces the symplastic and selective transport of nutrients across endodermis. This extracellular structure can be found in the roots of all higher plants and is thought to provide the protection of vascular tissues. In Arabidopsis, a genetic toolbox regulating the formation of Casparian strips has emerged recently. However, Arabidopsis has the stereotypical root which is much simpler than most other plant species. To understand the Casparian strip formation in a more complex root system, we examined CS regulatory pathways in tomato. Our results reveal a spatiotemporally conserved expression pattern of most essential components of CS machinery in tomato. Further functional analyses verify the role of homologous CS genes in the Casparian strip formation in tomato, indicating the functional conservation of CS regulatory cascade in tomato.

Highlighting reactive oxygen species as multitaskers in root development

“…Their interaction with PRX64 and RBOHF and determine their precise localization at the CSs development site. CASP1 guides this localization by interacting with SGN1 and SGN3 ( Alassimone et al, 2016 ; Li et al, 2018a ) MYB domain protein 36 (MYB36) (AT5G57620) Leaves, roots endodermis, lateral root and seedlings. Directly upregulated by SCR It promotes differentiation of the endodermis during root development.…”

Chemical components, physiological functions and regulation mechanism of plant Casparian strips

“…MYB36基因发挥同样的作用, 调控凯氏带的形成, 这为 解析番茄凯氏带的功能和形成的分子机制提供了坚实 的基础 [46] . 因此, 详细阐明凯氏带发挥功能的分子调 控机制, 对于通过利用生物工程手段进行农林植物性 状的改良具有深远的意义.…”

Genes for ash tree resistance to an insect pest identified via comparative genomics

“…AT4G37650/SHR is essential for root ground tissue patterning and interacts with SCARECROW/SCR 180 ; they are thought to function as transcriptional regulators 180 . The putative orthologue of OG20520/FRAEX38873_v2_000382300 in S. lycopersicum is Solyc02g092370; this gene is also known as SlSHRa and is involved in root radial patterning 181 . The putative orthologue from Populus trichocarpa, Potri.007G063300 (being the only P. trichocarpa gene belonging to the same OrthoMCL cluster as FRAEX38873_v2_000382300 11 ), is also known as PtSHR1 182 and down-regulation of this gene in transgenic hybrid poplar leads to increased height and girth, indicating that SHR is involved in regulation of cell division and meristem activity in shoots as well as roots 183 .…”