miR319b-JmGAMYB模块在胡桃楸花发育过程中的调控机制OA北大核心CSTPCD

Juglans mandshurica Maxim.is a woody fruit and timber tree species with broad application prospects.Its reproductive characteristics of monoecious and heterodichogamous effectively avoid self-fertilization.However,the regulatory mechanism of heterodichogamous flower development remains unclear.The miR319 family has been identified as one of the key miRNA families regulating flower bud differentiation in multiple plants.Our research group has screened and identified Jm-miR319b as a crucial miRNA regulating the flower development process of J.mandshurica,and GAMYB has been predicted as a target gene of Jm-miR319b.In order to explore the regulatory mechanism of miR319-GAMYB module on the flower development process of J.mandshurica,in this study,we screened the CDS sequences of GAMYB of J.mandshurica by transcriptome data,and verified the relationship of Jm-miR319b with the RLM 5'RACE technique.The target relationship between Jm-miR319b and GAMYB of J.mandshurica was verified using RLM 5'RACE technique.The full-length CDS of JmGAMYB gene was cloned by PCR gene amplification technique and analysed bioinformatically,and the expression of the target gene,GAMYB,was investigated in different organs and tissues and at different stages of development of the two reproductive types of J.mandshurica using qRT-PCR technique.The target gene GAMYB was analysed by qRT PCR in different organ tissues of J.mandshurica and in different developmental periods of both reproductive types.The results showed that the JmGAMYB gene was 1503 bp in length,encoding 500 amino acids.miR319b,a gene related to floral development,was directly targeted to JmGAMYB,with the opposite expression trend,and the cleavage site was at bases 10-11 of the miR319b maturation body.qRT-PCR quantification showed that the JmGAMYB gene was expressed in the stem,stem,and stem buds of J.mandshurica,and in the male and female buds of both reproductive types.JmGAMYB gene was expressed in stems,leaves,male and female flowers,and fruits of J.mandshurica,and the highest expression was found in male flowers.JmGAMYB gene expression was significantly different in male and female flower buds of male and female precursors during the physiological differentiation stage,and the expression of the JmGAMYB gene also reached the highest peak when male and female flowers were alternately opened during the morphological differentiation stage.Therefore,it is hypothesized that JmGAMYB is involved in the whole process of floral development in J.mandshurica and starts to play a regulatory role at the early stage of bud differentiation,with the highest relative expression at the time of pollination of male flowers,and then the expression starts to decrease after pollination.The results of this study will lay a foundation for further exploration of the molecular regulation mechanism of flower development in J.mandshurica.