pool of stem prison cell in the apical meristem of plants are key to continued growth and growth . Understanding how these theme cells are maintained and balanced against tell cellular phone could lead to method for increasing harvest yield and biomass .
Purdue University scientists have uncovered a key signaling cascade that maintain a balance between those stem cell and differentiated cellular phone . Yun Zhou , an adjunct prof in the Department of Botany and Plant Pathology and the Purdue Center for Plant Biology , and Han Han , a postdoctoral researcher in Zhou ’s lab , together with other colleagues published their results Thursday ( March 5 ) in the journal Nature Communications .
One microRNA cistron , show in green , is specifically activate by Arabidopsis thaliana Meristem Layer 1 ( ATML1 ) in the outermost layer of a plant shoot apex . This microRNA determines the concentration gradient of Hairy Meristem ( HAM ) genes , which controls stem prison cell function and check plants make leave-taking , peak and other organs . ( photograph courtesy of Yun Zhou )
uniform stem cells are locate in the meristems — the apex or tips of plant shoots and roots . These assist as a cant of undetermined cells that support plant growth and give ascent to unlike organs such as leaves or flower .
Zhou ’s previous work at Purdue showed that the apical - basal gradient of gene expression is essential to keep these stem cell alive in the outmost electric cell layers and their differentiate issue at internal tissues . Disturbing that slope leads to grievous flaw in stem - cellular telephone proliferation and specialization , affecting shoot ontogenesis and replica . Now , Zhou ’s lab has shown how that gradient is initiated and maintained .
Zhou ’s chemical group launch that the Arabidopsis thaliana Meristem Layer 1 ( ATML1 ) family of genes immediately activates a group of microRNAs in the epidermis of plants . These microRNAs mapping as a fluid signaling that specifically deactivates the Hairy Meristem ( HAM ) gene . These gammon genes are crucial to maintain the balance between the stem cubicle and differentiated cells .
In the epidermis , this mathematical group of microRNAs are actively synthesized and the microRNA level is high , eliminating most or all of the HAM genes and keep the stem cells . But as the microRNA digs profoundly into the upcountry cubicle layers , there is less of it to inactivate HAM , keep HAM concentrated in the basal neighborhood of meristems .
“ This is a spacial and worldly regulation lead to the gradient we ’ve seen , ” Zhou say , “ Our results uncover a molecular gene linkage between the epidermis and inject stem - prison cell homeostasis . We find that plant epidermis produces roving signals to control this gradient and the stem - cell activity . This may spread a Modern avenue for crop advance in the time to come . ”
The team ’s work combines in vivo alive imaging , in vitro biochemistry and in silico , or 3D computational , modeling .
Zhou ’s lab will continue explore the canonical functions of meristem exploitation and sustentation in an effort to develop methods to curb them to increase plant biomass and output . Purdue University , including the Purdue Center for Plant Biology , funded the research .
generator : Purdue University ( Brian Wallheimer )
