Study On Auxin Pathway In Rice Callus Induction

Rice,as a monocotyledonous model plant,is one of the few crops to achieve mature tissue culture,but the physiological processes and specific molecular mechanisms in tissue culture are still poorly understood.The current research on the induction of Arabidopsis callus found that the regulatory mechanism formed by the IAA gene family and the ARF gene family in the auxin pathway and the LBD gene family activated and transcribed by the ARF transcription factor has a regulatory effect on callus.The induction process plays an important role.The research in this paper found that there are similar regulatory mechanisms in rice,which play an important role in the process of callus induction of rice seeds.In this study,we constructed the CRL1 gene overexpression and gene knockout vectors of the rice LBD gene family,transformed Zhonghua 11 rice callus,and obtained5 transgene overexpression families and 8 transgene knockout families.Through callus induction experiments on genetic material seeds,it was found that there was no significant difference between the CRL1 gene over-expression material and the control group,but the callus induction of the CRL1 gene knockout material was strongly inhibited,and RNA interference with the known rice Os IAA10 The material phenotype is similar.In order to study the relationship between the two,the study first conducted a subcellular localization experiment.The results showed that Os IAA10 was localized on the nucleus and cell membrane at the same time.Colony PCR and sequencing of a large number of mutant strains obtained from the yeast two-hybrid screen library experiment revealed that Os IAA10 only It can interact with Os ARF5,17,21,23 among the many members of the Os ARF family.The CRL1 gene promoter was used as a bait to construct a vector.The yeast single-hybrid point-to-point experiment showed that only Os ARF5 and Os ARF21 of these four transcription factors can specifically bind to the Aux RE motif in the promoter region of the CRL1 gene and activate CRL1 gene transcription.The results of this study explored the specific molecular mechanism of rice callus induction,proved that rice callus induction is related to the CRL1 gene that controls crown root development,and also proved the callus of dicotyledonous plants andmonocotyledonous plants.There is a conservative regulatory mechanism.It is of great significance to deeply understand the process of rice tissue culture and improve the tissue culture ability of different rice varieties.