Tobacco Trichome Protein TTG2 And Auxin-Repressed Protein ARP1 Regulate Growth And Disease Resistance

The relationship between defense response and growth on plant was similar to human "war and peace", and disease resistance must submit to growth and development. When plant was attacked by plant pathogens, it can quickly mobilize defense mechanisms, effectively resist the occurrence and development of pathogens. After pathogen infection and pathogenicity has been effectively controlled, defense response fall as soon as possible, and plant growth process to restore normal. This process involves a variety of signal transduction pathway of plant hormones and non-hormone, and NtTTG2 and ARP1 play an important role in this confrontation relationship. The research was on NtTTG2 regulates growth and development and ARP1 regulates growth and disease resistance in tobacco.1. NtTTG2 regulates growth and development in TobaccoTRANSPARENT TESTA GLABRA (TTG) proteins is an important factor functions in regulating growth and development and disease resistance. The NtTTG2 gene silencing causes repressive effects on the vegetative growth, floral anthocyanin synthesis, flower colorization, and seed production. By contrary, the plant growth and development processes are promoted by NtTTG2 overexpression. Experiment results show that the NtTTG2 plays an important role in the process of growth and development. In contrast to the NtTTG2 negatively regulate tobacco disease resistance effect, it positively regulate tobacco growth and development.Using the real-time PCR to measure the expression of EXP1, EXP2, DFR and ANS related genes. Corresponding with the growth phenotype, the expression of EXP1, EXP2, DFR and ANS was lower in NtTTG2 silencing plant than wild-type, by contrast the expression of EXPl, EXP2, DFR and ANS was higher in NtTTG2 overexpression plant than wild-type. According to the expression of EXP1 and EXP2, it indicate that EXP1 and EXP2 play a certain role in NtTTG2 mediated vegetative growth of tobacco. And the expression of DFR and ANS were dependent on NtTTG2.2. ARP1 Regulates Growth and Disease Resistance in TobaccoARP1 was a Auxin-Repressed Protein. Based on gene silencing and overexpression analyses, and observe the disease conditions infected by viruses, bacteria and fungi, found that silencing ARP1, enhanced the growth but decreased the disease resistance. In contrast, overexpression of ARP1 can decreased the growth and enhanced the disease resistance.In order to further study the role the ARP1 played on relationship between the growth and disease resistance, we treated tobacco by the PAMPs. ARP1 resembles pathogen-associated molecular patterns and is required for them to repress plant growth and activate plant immunity responses.