| Soybean is an important cash crop with dual use of grain and oil.Due to the low yield per unit area and low planting efficiency,soybean production in China has been unable to meet the strong domestic demand,and the serious supply gap can only rely on import.Microtubules,as basic components of cytoskeleton,not only play an important role in tissue structure and cell division,but also play an important role in adaptive regulation of plants to stress environment.In this paper,the effects of different microtubule genes on growth and development of soybean were studied,in order to provide theoretical basis for breeding new soybean varieties with high yield and stress resistance.In this paper,soybean microtubule genes were identified and classified by bioinformatics analysis.Eight mutants encoding genes related to soybean microtubules and microtubule packaging proteins were obtained by screening soybean mutant library in laboratory.Plant phenotypes,microtubule structures and cell structures of 8 mutants were analyzed,and different effects of these microtubule gene mutations on leaf type,leaf color,plant type,microtubule arrangement and cell size and morphology of different tissue structures of soybean were found.These studies provided important experimental materials and theoretical basis for the identification and functional analysis of soybean microtubule genes.The research contents are as follows:1.Thirty-six soybean microtubule-related genes were identified by bioinformatics analysis and Arabidopsis microtubule gene evolution analysis,including 13 α-tubulin protein-coding genes,18 β-tubulin protein-coding genes and 5γ-turcs complex protein-coding genes.2.Screening laboratory mutant library,soy protein microtubules and microtubule packaging 8 mutant genes: including microtubule associated mutant 4:Gmtua1,Gmtub1,Gmtub2,Gmtub3;Microtubule binding protein related mutant 4:Gmkac1,Gmgcp2,Gmgcp3,Gmgcp4.3.Ala to Val mutation occurred in GmTUA1 gene(Glyma.05G110200)at the104 th amino acid position in GmTUA1 mutants.The GmTUA1 mutant showed different leaf type development and slender leaves.The arrangement of microtubules;The cells in xylem are small and loosely arranged;Further comparison of the changes in myeloid cells showed that the length-width ratio of GmTUA1 myeloid cells was significantly higher than that of wild type,and myeloid cells were elongated and narrowed.4.In the GmTUB1 mutant(Glyma.01G109300),the mutation of Asn to Tyr occurred at the 89 th amino acid position.The color of GmTUB1 mutant guide leaf changed and the leaf yellowed.The cells in the xylem are small and loosely arranged.5.Ser to Cys mutation occurred in GmTUB2 gene(Glyma.20G159200)at the382 nd amino acid position in GmTUB2 mutant.The mutation in this position resulted in stunted plants,shriveled leaves and stunted growth and development of GmTUB2 mutants.Microtubule arrangement disorder;The cells in xylem are small and loosely arranged;The myeloid cells of GmTUB2 mutants were disordered and small.6.In Gmtub3 mutants,GmTUB3,GmTUB4 and GmTUB5 were mutated simultaneously,among which GmTUB3(Glyma.15G263900)was mutated from Ala to Thr at the 207 th amino acid position.GmTUB4 gene(Glyma.08G054000)has a Ser to Asn mutation at the 352 nd amino acid position.GmTUB5 gene(Glyma.19G253300)has a mutation from Ala to Val at the 238 th amino acid position.Gmtub3 plant leaves slender;The cells in xylem are small and loosely arranged;There was no significant difference in the ratio of length to width of Gmtub3 myeloid cells compared with the wild type.7.Ala to Thr mutation of GmKAC1 gene(Glyma.01G023600)occurred at the position 312 of amino acid in GmKAC1 mutant,resulting in yellow leaf of GmKAC1 and irregular arrangement of microtubules.The xylem cells are small and loosely arranged.The ratio of length to width of myeloid cells of GmKAC1 was significantly increased and the cells were elongated.8.Trp mutation occurred in GmGCP2 gene(Glyma.03G090100)at the 470 th amino acid position in GmGCP2 mutants,which resulted in dwarf plants and slow growth of GmGCP2 mutants.Microtubule structure arrangement rule;The cells in xylem were few and small and loosely arranged.The myeloid cells of GmGCP2 were smaller than those of the wild type,but the shape of myeloid cells was not significantly different from that of the wild type.9.GmGCP3 gene(Glyma.04G031800)changed from Pro to Ser at the 236 th amino acid position,resulting in disordered microtubule arrangement in GmGCP3 mutants.The cells in xylem were few and small and loosely arranged.Further comparing the changes of myeloid cells,the length and width of myeloid cells of GmGCP3 mutant were significantly higher than that of the wild type,and the cells were narrower and longer.10.GmGCP4(Glyma.02G017400)changed from Arg to Trp amino acid at the position of the 50 th amino acid in GmGCP4 mutants,which resulted in the increase of the pitch between GmGCP4 plants.Disordered arrangement of microtubules;The cells in xylem are small and loosely arranged.The length-width ratio of myeloid cells of GmGCP4 mutant was significantly higher than that of wild type,and the cells were narrow and long.11.In conclusion,mutations of GmTUB2,GmKAC1,GmGCP3 and GmGCP4 genes affect microtubule structure,microtubule arrangement and cell morphology composition.GmTUA1,GmTUB3,GmTUB4 and GmTUB5 play an important role in the development of leaf type.GmTUB1 and GmKAC1 can regulate the leaf color of soybean,and the deletion of GmTUB1 and GmKAC1 causes leaf yellowing.GmTUB2,GmGCP2 and GmGCP4 affected plant type development of soybean.Microtubule-related genes play an important role in the formation of tissue structure and the development of leaf and plant type in soybean. |
