Transcriptome profiling reveals the candidate genes associated with aroma metabolites and emission of pear (Pyrus ussuriensis cv.)

Abstract

Transcriptome profiling reveals the candidate genes associated with aroma metabolites and emission of pear (Pyrus ussuriensis cv.) ଝ a b s t r a c t Aroma is an important factor affecting pear fruit quality. However, the molecular basis for the development of aroma metabolites and their emission is poorly understood. Unripe 'Nanguoli' pear fruit has poor aroma, while the ripe fruit has an intense aroma, and calcium treatment can enhance the aroma, providing good material for transcriptome analysis.Digital gene expression (DGE) analysis of 'Nanguoli' fruit was performed at three important developmental stages, with and without calcium treatment, six libraries in total. Of the total number of mapped reads (11.4-13.6 million), an average of 69.81% could be mapped to the pear genome. A total of 10,776 differentially expressed genes between the poor aroma and intense aroma were categorized into 36 functional groups and 37 pathways according to GO and KEGG databases, respectively. Genes more highly expressed in the more aromatic fruit include some from the fatty acid pathway such as FAD, ADH, PDC, LOX, and lipase genes. Some transcription factors were identified with high correlation to aroma biosynthesis in pear. Also, ABA may play an important role in the calcium-triggered improvement of 'Nanguoli' aroma. In addition, candidate genes were verified with quantitative real-time PCR.

Identification of candidate genes related to aroma in rice by analyzing the microarray data of highly aromatic and nonaromatic recombinant inbred line bulks

“…1). Consistent with these results of GO enrichment analysis, all biological categories except the biological process "death (GO: 0016265)" have been previously reported in a study conducted by Wei et al (2016) on aroma metabolites and emission of pear. Our results indicated that the biological process "death" might be related to aroma formation in rice in addition to other reported biological processes.…”

“…The enrichment analysis of cellular component revealed that three categories were enriched by differentially expressed genes. In accordance with these results of GO enrichment analysis, all cellular component categories including membrane-enclosed lumen (GO : 0031974), macromolecular complex (GO : 0032991), and organelle part (GO : 00044422) have been previously reported in a study by Wei et al (2016).…”

“…According to the enrichment analysis of molecular function, seven categories were enriched by differentially expressed genes. Consistent with these results of GO enrichment analysis, six out of seven molecular function categories including binding (GO : 0005488), enzyme regulator activity (GO : 0030234), structural molecule activity (GO : 0005198), transporter activity (GO : 0005215), antioxidant activity (GO : 0016209), and catalytic activity (GO : 0003824) have been previously reported in a study conducted by Wei et al (2016) on aroma metabolites and emission of pear. The molecular function "transcription regulator activity (GO : 0030528)" has not been previously reported as associated with aroma.…”

Metabolome and Transcriptome Reveal Novel Formation Mechanism of Early Mature Trait in Kiwifruit (Actinidia eriantha)

“…Fruit maturation is a complex physiological process, which is accompanied by a series of biochemical processes such as sugar accumulation (Zhang Y.J. et al, 2014;Xu et al, 2020), acid reduction (Jiang et al, 2020), aroma production (Wei et al, 2016), pigment accumulation (Gan et al, 2019), flavonoid metabolism (Huang et al, 2020), and endogenous hormone change (Wang et al, 2016). The difference of fruit quality between early mature and late mature cultivar in our study was mainly reflected in the SSC, DM, and pigment contents.…”

Exploring the Aroma Fingerprint of Various Chinese Pear Cultivars through Qualitative and Quantitative Analysis of Volatile Compounds Using HS-SPME and GC×GC-TOFMS

“…Regarding Pyrus ussuriensis Maxim aroma evaluation, some scholars have evaluated the types, quantity, and volatile content of the aroma in Pyrus ussuriensis Maxim, including Nanguoli, Huaguai, and Jianbali [ 13 , 20 , 21 ], mainly using headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) technology. Some researchers have also studied the physiological mechanism of aroma formation and release in “Nanguoli” fruit and identified relevant candidate genes via calcium regulation, providing valuable data for further research into the molecular mechanism of pear fruit aroma regulation [ 19 ]. However, the number of aroma components reported in Pyrus ussuriensis Maxim is still limited, and the analysis of aroma characteristics has not been adequately reported.…”