Overexpression of Pear (Pyrus pyrifolia) CAD2 in Tomato Affects Lignin Content

PpCAD2 was originally isolated from the ‘Wangkumbae’ pear (Pyrus pyrifolia Nakai), and it encodes for cinnamyl alcohol dehydrogenase (CAD), which is a key enzyme in the lignin biosynthesis pathway. In order to verify the function of PpCAD2, transgenic tomato (Solanum lycopersicum) ‘Micro-Tom’ plants were generated using over-expression constructs via the agrobacterium-mediated transformation method. The results showed that the PpCAD2 over-expression transgenic tomato plant had a strong growth vigor. Furthermore, these PpCAD2 over-expression transgenic tomato plants contained a higher lignin content and CAD enzymatic activity in the stem, leaf and fruit pericarp tissues, and formed a greater number of vessel elements in the stem and leaf vein, compared to wild type tomato plants. This study clearly indicated that overexpressing PpCAD2 increased the lignin deposition of transgenic tomato plants, and thus validated the function of PpCAD2 in lignin biosynthesis.

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PpNAC187 Enhances Lignin Synthesis in ‘Whangkeumbae’ Pear (Pyrus pyrifolia) ‘Hard-End’ Fruit

Molecules ◽

10.3390/molecules24234338 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4338

Author(s):

Mingtong Li ◽

Chenxia Cheng ◽

Xinfu Zhang ◽

Suping Zhou ◽

Caihong Wang ◽

...

Keyword(s):

Transgenic Tobacco ◽

Lignin Content ◽

Lignin Biosynthesis ◽

Phenylpropanoid Pathway ◽

Pyrus Pyrifolia ◽

Rna Seq ◽

Pear Fruit ◽

Nac Transcription Factors ◽

Vessel Elements ◽

Leaf Tissues

A disorder in pears that is known as ‘hard-end’ fruit affects the appearance, edible quality, and market value of pear fruit. RNA-Seq was carried out on the calyx end of ‘Whangkeumbae’ pear fruit with and without the hard-end symptom to explore the mechanism underlying the formation of hard-end. The results indicated that the genes in the phenylpropanoid pathway affecting lignification were up-regulated in hard-end fruit. An analysis of differentially expressed genes (DEGs) identified three NAC transcription factors, and RT-qPCR analysis of PpNAC138, PpNAC186, and PpNAC187 confirmed that PpNAC187 gene expression was correlated with the hard-end disorder in pear fruit. A transient increase in PpNAC187 was observed in the calyx end of ‘Whangkeumbae’ fruit when they began to exhibit hard-end symptom. Concomitantly, the higher level of PpCCR and PpCOMT transcripts was observed, which are the key genes in lignin biosynthesis. Notably, lignin content in the stem and leaf tissues of transgenic tobacco overexpressing PpNAC187 was significantly higher than in the control plants that were transformed with an empty vector. Furthermore, transgenic tobacco overexpressing PpNAC187 had a larger number of xylem vessel elements. The results of this study confirmed that PpNAC187 functions in inducing lignification in pear fruit during the development of the hard-end disorder.

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Response of Fruit Bagging to Lignin Biosynthesis and Expression of Related Genes in Fruit Peel of Sand Pear (Pyrus pyrifolia Nakai) cv. Cuiguan

HortScience ◽

10.21273/hortsci14382-19 ◽

2019 ◽

Vol 54 (11) ◽

pp. 1989-1997

Author(s):

Chun-hui Shi ◽

Xiao-qing Wang ◽

Xue-ying Zhang ◽

Lian-ying Shen ◽

Jun Luo ◽

...

Keyword(s):

Lignin Content ◽

Quantitative Polymerase Chain Reaction ◽

Green Light ◽

Lignin Biosynthesis ◽

Cinnamyl Alcohol Dehydrogenase ◽

Pyrus Pyrifolia ◽

Fruit Peel ◽

Lignin Synthesis ◽

Yellow Orange ◽

Coa Reductase

This study explored the effects of different colored bags (blue, green, white, yellow, orange, and red) on russet deposition on the peel of semi-russet ‘Cuiguan’ pears 10 days after full bloom (DAFB). The process of russeting of the peel and structure of the cork layer were characterized by microscopy and scanning electron microscopy (SEM), followed by the detection of lignin and the activity of enzymes involved in lignin synthesis. The expression of cinnamate-4-hydroxylase, 4-coumarate:coenzyme A ligase, cinnamyl alcohol dehydrogenase, cinnamoyl-CoA reductase, and peroxidase, which were related to phenylalanine ammonia-lyase, was determined via real-time quantitative polymerase chain reaction. Russeting of the outer peel of ‘Cuiguan’ pear accumulated rapidly at 80 DAFB, and a positive relationship between the russet index and lignin content was observed. Red and infrared (IR) ray, partial far-IR light (600–800 nm), and ultraviolet-A light (350–400 nm) promoted russeting in ‘Cuiguan’ pear peel, whereas green light decreased russeting, the russet index, enzymatic activities, and the expression levels of enzymes involved in lignin synthesis. Values of all these factors were higher for ‘Cuiguan’ pears in red bags than for those in bags of other colors. These findings suggested that spectral components affected the synthesis of lignin and the formation of fruit russet. Storage in green bags reduced russeting and improved fruit appearance.

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PpNAC187 enhances lignin synthesis in ‘Whangkeumbae’ pear (Pyrus pyrifolia) ‘hard-end’ fruit

10.21203/rs.2.11046/v1 ◽

2019 ◽

Author(s):

Mingtong Li ◽

Chenxia Cheng ◽

Xinfu Zhang ◽

Suping Zhou ◽

Caihong Wang ◽

...

Keyword(s):

Transgenic Tobacco ◽

Lignin Content ◽

Lignin Biosynthesis ◽

Phenylpropanoid Pathway ◽

Pyrus Pyrifolia ◽

Rna Seq ◽

Pear Fruit ◽

Nac Transcription Factors ◽

Vessel Elements ◽

Leaf Tissues

Abstract Background: A disorder in pears known as ‘hard-end’ fruit affects the appearance, edible quality, and market value of pear fruit. To explore the mechanism underlying the formation of hard-end, RNA-Seq was carried out on the calyx end of ‘Whangkeumbae’ pear fruit with and without the hard-end symptom. Result: Results indicated that genes in the phenylpropanoid pathway affecting lignification were up-regulated in hard-end fruit. An analysis of differentially expressed genes (DEGs) identified three NAC transcription factors, and RT-qPCR analysis of PpNAC138, PpNAC186 and PpNAC187 confirmed that PpNAC187 gene expression was correlated with the hard-end disorder in pear fruit. A transient increase in PpNAC187 was observed in the calyx end of ‘Whangkeumbae’ fruit when they began to exhibit hard-end symptom. Concomitantly, the higher level of PpCCR, Pp4CL and PpCOMT transcripts was observed; which are the key genes in lignin biosynthesis. Notably, lignin content in the stem and leaf tissues of transgenic tobacco overexpressing PpNAC187 was significantly higher than in control plants transformed with an empty vector. Furthermore, transgenic tobacco overexpressing PpNAC187 had a larger number of xylem vessel elements. Conclusion: The results of this study confirmed that PpNAC187 functions in inducing lignification in pear fruit during the development of the hard-end disorder.

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Accumulation of Vitamin C and Enhanced Tolerance to Iron Deficiency Stress in Transgenic Tomato with GalUR Gene

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.749.277 ◽

2013 ◽

Vol 749 ◽

pp. 277-282 ◽

Cited By ~ 1

Author(s):

Jing Hui Yang ◽

Yan Jun Liu ◽

Jun Xun Huang ◽

Jian Ke Li ◽

Yan Yu Shi ◽

...

Keyword(s):

Iron Deficiency ◽

Vitamin C ◽

Environmental Stress ◽

Plant Height ◽

Biosynthetic Pathway ◽

Fold Increase ◽

Transgenic Tomato ◽

Tomato Plants ◽

Over Expression ◽

Transgenic Tomato Plants

The genes dominating vitamin C (AsA) synthesis in strawberry fruits may be used in increasing levels of AsA and tolerance to environmental stress in other plants by transgenic method. D-galacturonate reductase (GalUR) plays a prominent role in the regulation of the AsA biosynthetic pathway. In this study, transgenic tomato plants (Tg1, Tg2) overexpressing strawberry GalUR gene have been developed and resulted in 2.6-fold increase of AsA in fruits and 1.6-fold increase of AsA in leaves over non-transformed tomato (WT) and the levels of AsA were positively correlated with increased GalUR activity. Moreover, Tg1, Tg2 showed enhanced tolerance to iron deficiency as compared to WT. Under Fe (II) deficiency condition the plant height of Tg1, Tg2 was 1.2-1.7 times, AsA content of Tg1 was 1.8-2.8 times and Fe (II) content of Tg1 was 1.1-1.4 times as much as WT. Otherwise, AsA content of transgenic FRO2 plant (TFRO2) was more than WT but less than Tg1 and its Fe (II) content was more than WT and Tg1. The study demonstrated that the over-expression of GalUR gene enhanced the level of AsA and Fe (II) of transgenic tomato plants which had better growth than WT under iron stresses. Therefore, GalUR and FRO should be interrelate and stimulative each other.

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