Genomics and Applied Biology 2019, Vol.10, No.1, 1-9
1
Research Article
Open Access
miRNA Analysis of Leaves of “Zijuan” Tea (
Camellia sinensis
) Based on
High-throughput Sequencing
Song Weixi
1, 2
, Xia Lifei
1, 2
, Tian Yiping
1, 2
, Jiang Huibin
1, 2
, Sun Yunnan
1, 2
, Liu Dehe
1, 2
, Chen Linbo
1, 2
1 Tea Research Institute, Yunnan Academy of Agricultural Sciences, Yunnan Engineering Research Center of Tea Germplasm Innovation and Matching
Cultivation, Menghai, 666201, China
2 Yunnan Provincial Key Laboratory of Tea Science, Menghai, 666201, China
Corresponding author email:
Genomics and Applied Biology, 2019, Vol.10, No.1 doi:
Received: 24 Sep., 2018
Accepted: 30 Oct., 2018
Published: 25 Jan., 2019
Copyright © 2019
Song et al., This article was first published in Genomics and Applied Biology (2018, 06: 2489-2497) in Chinese, and here was
authorized to translate and publish the paper in English under the terms of Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Song W.X., Xia L.F., Tian Y.P., Jiang H.B., Sun Y.N., Liu D.H., and Chen L.B., 2019, miRNA analysis of leaves of “Zijuan” tea (
Camellia sinensis
) based
on high-throughput sequencing, Genomics and Applied Biology, 10(1): 1-9 (doi:
Abstract
“Zijuan” is specific tea resource with abundant secondary metabolites, like catechins, anthocyanins, flavonoids, etc. Its
biosynthesis is a network of multiple metabolic pathways connected by associated nodes, which is controlled by a variety of
structural and regulatory genes. MicroRNAs (miRNAs), as a non-coding RNAs, play important roles in plant growth, development
and secondary metabolism by regulating gene expression. In this study, four independent miRNA libraries of bud, second-leaf, open
surface leaf and mature-leaf of “Zijuan” tea were constructed and sequenced by high-throughput sequencing. 126 known miRNAs
were identified and divided into 26 families, and 119 novel miRNAs were predicted. Based on the transcriptome data of “Zijuan” tea,
724 and 2,285 target genes were predicted for known and novel miRNAs, respectively. The predicted target genes were mostly
transcription factors, which included MYB and bHLH transcription factors for regulating the biosynthesis of secondary metabolites -
anthocyanins and flavonoids. All the above results would provide a theoretical basis for further studies on miRNA regulating the
development of tea leaf and the biosynthesis of secondary metabolites in
Camellia sinensis
.
Keywords
“Zijuan”
Camellia sinensis
(L.); High-throughput sequencing; miRNA; Target genes
Background
Camellia sinensis
(L.) is an important cash crop for leaf use. It contains a large amount of tea polyphenol (TP), a
secondary metabolite, which is beneficial to human health. TP is an important component that determines the
quality and health efficacy of tea. The content of TP is about 18%~36% of the dry weight of young buds, in which
catechin is about 70% of the total tea polyphenols (Xia and Gao, 2009). “Zijuan” is a special tea resource, its
young bud leaves are purple. Not only its catechin content is high, but its anthocyanin content is 10 times higher
than that of common tea (Cai et al., 2010). Catechin and anthocyanin are both flavonoid compounds. The
biosynthesis of catechins and anthocyanins is a network of multiple metabolic pathways connected by associated
nodes, which is controlled by a variety of structural and regulatory genes.
MicroRNA, also known as miRNAs, is an endogenous non-coding single-stranded small molecule RNA, which
exists widely in organisms and is composed of about 21~25 nucleotides (Bartel, 2004). In 1993, miRNA lin-4 was
cloned for the first time in
Caenorhadits elegans
, and it was found that miRNA lin-4 played an important role in
postembryonic development (Lee et al., 1993). Later, a large number of miRNA were found in the model plant of
Arabidopsis thaliana
(Sunkar and Zhuwei, 2004), rice (Sunkar et al., 2005) and crops, such as maize (Mica et al.,
2006), cotton (Kwak et al., 2009) and soybean (Xu et al., 2013). It had been shown that miRNA could recognize
target gene mRNA by complementary pairing with target mRNA, and degrade target mRNA or inhibit target
mRNA translation at the transcriptional level, thereby regulating the abundance and function of target mRNA
(Bartel, 2004). In plants, miRNAs could regulate organogenesis and differentiation, metabolism, growth and
development, signal transduction of hormones, response to abiotic stress and biological stress and other biological
processes (Zhang et al., 2007; Kwak et al., 2009; Xu et al., 2013).
