MicroRNAs and their targeted genes associated with phase changes of stem explants during tissue culture of tea plant

Abstract

Elucidation of the molecular mechanism related to the dedifferentiation and redifferentiation during tissue culture will be useful for optimizing regeneration system of tea plant. In this study, an integrated sRNAome and transcriptome analyses were carried out during phase changes of the stem explant culture. Among 198 miRNAs and 8001 predicted target genes, 178 differentially expressed miRNAs and 4264 potential targets were screened out from explants, primary calli, as well as regenerated roots and shoots. According to KEGG analysis of the potential targets, pathway of “aminoacyl-tRNA biosynthesis”, “proteasome” and “glutathione metabolism” was of great significance during the dedifferentiation, and pathway of “porphyrin and chlorophyll metabolism”, “mRNA surveillance pathway”, “nucleotide excision repair” was indispensable for redifferentiation of the calli. Expression pattern of 12 miRNAs, including csn-micR390e, csn-miR156b-5p, csn-miR157d-5p, csn-miR156, csn-miR166a-3p, csn-miR166e, csn-miR167d, csn-miR393c-3p, csn-miR394, csn-miR396a-3p, csn-miR396 and csn-miR396e-3p, was validated by qRT-PCR among 57 differentially expressed phase-specific miRNAs. Validation also confirmed that regulatory module of csn-miR167d/ERF3, csn-miR156/SPB1, csn-miR166a-3p/ATHB15, csn-miR396/AIP15A, csn-miR157d-5p/GST and csn-miR393c-3p/ATG18b might play important roles in regulating the phase changes during tissue culture of stem explants.

Relationship between Secondary Metabolism and miRNA for Important Flavor Compounds in Different Tissues of Tea Plant (Camellia sinensis) As Revealed by Genome-Wide miRNA Analysis

“…19 In tea plant, miR166a-3p was considered to be involved in the regulation of stem explant dedifferentiation and redifferentiation. 35 In our data, the expression levels of miR166c, miR166h, and miR166j were higher in bud than in lateral root, which may have the same function as previously reported for miR166a-3p. In the research about miRNAs related to the sprout development of tea plant cultivar "Pingyang Tezaocha", 21 related DEmiRNAs were found.…”

“…In leaf development, miRNA166 was shown to regulate the polarity of maize leaf through hd-zipIII family member rolled leaf1 ( rld1 ) . In tea plant, miR166a-3p was considered to be involved in the regulation of stem explant dedifferentiation and redifferentiation . In our data, the expression levels of miR166c, miR166h, and miR166j were higher in bud than in lateral root, which may have the same function as previously reported for miR166a-3p.…”

miRNA expression profiling and zeatin dynamic changes in a new model system of in vivo indirect regeneration of tomato

“…Low expression levels of sly-miR166c-5p and sly-miR166c-3p were observed during the change from stem to callus stages in this study. Previous research has shown that miR166, together with miR156 and miR396 were down-regulated during callus formation from tea plant stem explants [ 73 ]. miR166 was identified to target Class III homeodomain leucine zipper (HD-Zip III) gene family of transcription factors, including REVOLUTA (REV), PHABULOSA (PHB), PHAVOLUTA (PHV), CORONA (CNA), and ATHB8 in Arabidopsis [ 43 ].…”

“…together with miR156 and miR396 were down-regulated during callus formation from tea plant stem explants [73]. miR166 was identified to target Class III homeodomain leucine zipper (HD-Zip III) gene family of transcription factors, including REVOLUTA (REV), PHABU-LOSA (PHB), PHAVOLUTA (PHV), CORONA (CNA), and ATHB8 in Arabidopsis [43].…”

MiRNA expression profiling and zeatin dynamic changes in a new model system ofin vivoindirect regeneration of tomato

“…Low expression levels of sly-miR166c-5p and sly-miR166c-3p were observed during the change from stem to callus stages in this study. Previous research has shown that miR166, together with miR156 and miR396 were down-regulated during callus formation from tea plant stem explants[77]. miR166 was identified to target Class III homeodomain leucine zipper (HD-Zip III) gene family of transcription factors, including REVOLUTA (REV), PHABULOSA (PHB), PHAVOLUTA (PHV), CORONA (CNA), and ATHB8 in Arabidopsis [49].…”