The Cotton GhRac6 Gene Encoding a Plant ROP/RAC Protein Improves the Plant Defense Response to Aphid Feeding
- 140 Downloads
The plant ROP/RAC protein belongs to a subfamily of Rho family GTPases that inimitably exists in plants. It is considered an all-powerful molecular switch that modulates various plant developmental processes and plant defense responses to multifarious stresses. However, their exact roles are currently not entirely clear. Herein, the role of GhRac6, a ROP/RAC member from Gossypium hirsutum, was explored in the plant defense response to aphid feeding using transgenic technology. The deduced sequence of the GhRac6 protein is highly homologous to that of ROP/RAC proteins from other plants. GhRac6 expression was significantly upregulated in cotton leaves after damage by cotton aphids or wounding. The results of choice and no-choice tests showed that the number of aphids on GhRac6-overexpressing transgenic Arabidopsis was more than that on wild-type plants, while the secreted quantity of aphid honeydew in transgenic Arabidopsis was less than that in wild-type plants. Furthermore, the soluble sugar content and the proline content were higher in transgenic than in wild-type Arabidopsis to a certain extent. The activity of PAL and CAT in transgenic Arabidopsis was also higher than that in wild-type plants. Callose deposits were more abundant in transgenic than in wild-type Arabidopsis. The expression of related defense genes in the salicylic acid signaling pathway was considerably higher in transgenic than in wild-type Arabidopsis. These results collectively demonstrated that the cotton ROP gene GhRac6 improved the plant defense response to aphid feeding by regulating some aphid resistance indexes.
KeywordsGhRac6 Gossypium hirsutum Arabidopsis Aphids Defense response
Suppression subtractive hybridization 62
Quantitative real-time polymerase chain reaction
Expressed sequence tag
Open reading frame
Murashige and Skoog
Polymerase chain reaction
Phenylalanine ammonia lyase
Z.J.M. and Y.Y.Z. designed the research. Y.Z., L.L., L.J.J., Y.S., and Z.G.H. performed the experiments. Y.Z., Z.J.M., and W.X.P. analyzed the data and wrote the manuscript.
This work was supported by a grant from the National Natural Science Foundation of China (Grant No. 31471783).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
- Asprodites N (2005) The cloning and characterization of two ROP/RAC G-proteins from Gossypium Hirsutum. Uni of New Orleans Theses and Dissertations. 233Google Scholar
- Chen JJ, Wang XF (2000) Plant physiol Exp guide. China Agriculture Press, Beijing (in Chinese)Google Scholar
- Duan CX, Peng GS, Wang XM, Zhu ZD (2013) Differences in the physiological response of resistant and susceptible rice varieties infested by the small brown planthopper. Chin J Appl Entomol 50:145–153Google Scholar
- Jin L, Mackey DM (2017) Measuring callose deposition, an indicator of cell wall reinforcement, during bacterial infection in Arabidopsis. In: Plant Pattern Recognition Receptors: Methods and Protocols. pp 195–205Google Scholar
- Li TT, Jiang WZ, Gu TT, Liu YY, Xu JP, Liu GJ, Cao CX (2016) Relationship between aphid-resistance and leaf nutrient content of cucumber. Shandong Agricul Sci 48:44–47 50Google Scholar
- Mony FTZ, Ali MS, Islam MN, Choudhury S, Hossain MS (2017) Effect of salicylic acid and varieties on incidence of aphid and yield of mustard (Doctoral dissertation)Google Scholar
- Pandey GK, Sharma M, Pandey A, Shanmugam T Emerging (2015) Roles of Rho GTPases in plants//GTPases. Springer International Publishing. pp 45–55Google Scholar
- Rasool B, McGowan J, Pastok D, Marcus SE, Morris J, Verrall SR, Foyer CH (2017) Redox control of aphid resistance through altered cell wall composition and nutritional quality. Plant Physiol 1–37Google Scholar
- Sharma I, Ahmad P (2014) Catalase: a versatile antioxidant in plants. Oxidative Damage to Plants. pp 131–148Google Scholar
- Zhou FC, Ren J, Chen XH, Yang AM, Hu QJ, Zhang JJ, He J (2014) The effects of Aphis gossypii sucking on the antibiotic substance in cucumber leaves. J Yangzhou Uni 35:99–103Google Scholar
- Züst T, Agrawal AA (2016) Mechanisms and evolution of plant resistance to aphids. Nat Plants 2:1–19Google Scholar