Studies On The Regulation Mechanism Of Arabidopsis Microfilament Binding Protein AtVLN1 On Root Hair Growth

Root hair development affects plant growth and development and environmental responses.Root hair development is regulated by the differentiation and growth of hair-producing cells(H cells).Ethylene plays a significant role in promoting root hair development.The Ateto1 mutant showed extremely dense root hair because of the increased ethylene production.The actin cytoskeleton plays an essential regulatory role in root hair development,but its mechanism of action has been poorly studied.AtVLN1 is an Arabidopsis actin bundling protein.This experiment explores the relationship between AtVLN1 and ethylene synthesis during root hair development,revealing the role of AtVLN1.We draw the following experimental results:1.PVLN1::GUS homozygous plants were obtained by vector construction and homozygote screening,and GUS staining showed that AtVLN1 was highly expressed in the roots of Arabidopsis thaliana.2.Using stereo microscope observation and statistical analysis,it was found that compared with Col-0,the root hair numbers of Atvln1-1 and Atvln1-2 significantly increased,and the root hair numbers of AtVLN1-OE #7 and AtVLN1-OE #8 significantly decreased.Further,compared with Col-0,AtVLN1-OE #7 and AtVLN1-OE #8 had significantly reduced H cells,Atvln1-1 and Atvln1-2 showed more H cell growth points.The above results indicate that AtVLN1 negatively regulates root hair development by regulating H cell differentiation and growth.3.Ethylene-specific agent treatments showed that ETH treatments significantly increased the root hair numbers of all plants,including activation of AtVLN1-OE #7,AtVLN1-OE #8 hair development.1-MCP treatment significantly reduced the root hair numbers of in all plants,including inhibition of root hair development of Atvln1-1 and Atvln1-2.Further,gas chromatography was used to detect the amount of ethylene produced in plant roots.Compared with Col-0,the amount of ethylene produced in Atvln1-1 and Atvln1-2was significantly increased,while AtVLN1-OE #7 and AtVLN1-OE #8 significantly decreased.These results indicate that AtVLN1 negatively regulates ethylene synthesis during root hair development.4.The expression of AtETO1 in Col-0,Atvln1-1,Atvln1-2,AtVLN1-OE #7,AtVLN1-OE#8 was detected by RT-q PCR.We found that compared to Col-0,.The expression level of AtETO1 was significantly reduced in roots of Atvln1-1 and Atvln1-2 and significantly increased in the roots of AtVLN1-OE #7 and AtVLN1-OE #8.Further,the root hair numbers of Atvln1 Ateto1 #1,Atvln1 Ateto1 #2,AtVLN1-OE Ateto1 #1,AtVLN1-OE Ateto1 #2 plantswere observed through a stereomicroscope.We found that compared with Col-0,all the constructed materials were root hair dense,similar to Ateto1-1.The above shows that during the development of root hair,AtVLN1 affects ethylene synthesis by regulating the expression of AtETO1.Based on the above results,this experiment firstly demonstrate that Arabidopsis actin bundling protein AtVLN1 plays a negative regulatory role in root hair development,and that it plays a role by affecting AtETO1 expression and ethylene synthesis.This study provides a new scientific basis for the function of AtVLN1 in vivo and the mechanism of plant root hair development.