Transcriptome analysis of ovary culture-induced embryogenesis in cucumber (Cucumis sativus L.)

Background. Ovary culture is a useful technique used to generate double haploid (DH) cucumber (Cucumis sativus L.) plants. However, cucumber ovary culture have a low rate of embryo induction and plant regeneration. Moreover, the cucumber embryogenesis mechanism remains unclear. In this study, we explored the molecular basis of cucumber embryogenesis in order to establish a foundation for a more efficient ovary culture method. Using transcriptome sequencing, we also investigated the differential expression of genes during the embryogenesis process. Methods. Cytological and morphological observations have divided cucumber ovary culture into three stages: early embryo development (T0), embryo morphogenesis (T1, T2, T3 and T4), and shoot formation (T5). We selected six key time points for transcriptome sequencing and analysis: T0 (the ovules were cultured for 0 d), T1 (the ovules were cultured for 2 d), T2 (the embryos were cultured for 10 d), T3 (the embryos were cultured for 20 d), T4 (the embryos were cultured for 30 d), and T5 (the shoots after 60 d culture). Results. We used cytology and morphology to observe the characteristics of the cucumber’s developmental transformation during embryogenesis and plant regeneration. The differentially expressed genes(DEGs) at developmental transition points were analyzed using transcriptome sequencing. In the early embryogenesis stage, the cells expanded, which was the signal for gametophytes to switch to the sporophyte development pathway. RNA-seq revealed that when compared to the fresh unpollinated ovaries, there were 3,468 up-regulated genes in the embryos, including hormone signal transduction genes, hormone response genes, and stress-induced genes. The reported embryogenesis-related genes BBM, HSP90 and AGL were also actively expressed during this stage. In the embryo morphogenesis stage (from cell division to cotyledon-embryo formation), 480 genes that functioned in protein complex binding, microtubule binding, tetrapyrrole binding, tubulin binding and other microtubule activities were continuously up-regulated during the T1, T2, T3 and T4 time points. This indicated that the cytoskeleton structure was continuously being built and maintained by the action of microtubule-binding proteins and enzyme modification. In the shoot formation stage, 1,383 genes were up-regulated that were mainly enriched in phenylpropanoid biosynthesis, plant hormone signal transduction, phenylalanine metabolism, and starch and sucrose metabolism. These up-regualted genes included six transcription factors that contained a B3 domain, nine genes in the AP2/ERF family, and two genes encoding WUS homologous domain proteins. Conclusions. Evaluation of molecular gynogenesis events may contribute to a better understanding of the molecular mechanism of cucumber ovarian culture.

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Analysis of differentially expressed genes during embryogenesis in ovary culture of cucumber (Cucumis sativus L.)

10.21203/rs.2.10287/v1 ◽

2019 ◽

Author(s):

Ying Deng ◽

Wenyuan Fu ◽

Bing Tang ◽

Lian Tao ◽

Lu Zhang ◽

...

Keyword(s):

Signal Transduction ◽

Cucumis Sativus ◽

Differentially Expressed Genes ◽

Shoot Formation ◽

Differentially Expressed ◽

Embryo Maturation ◽

Ovary Culture ◽

Cucumis Sativus L ◽

Microtubule Binding ◽

Formation Stage

Abstract Background: Ovary culture has been a useful way to generate double haploid (DH) plant in cucumber (Cucumis sativus L.). However, the rate of embryo induction is low, and the probability for the induced embryo to grow into normal embryo is low as well. This is largely due to unknown of the mechanism of embryogenesis in cucumber. In this study, the differentially expressed genes during embryogenesis, including the early stages of embryo formation, embryo maturation and shoot formation, was investigated with transcriptomic technique to set up basis for a more efficient ovary culture technology Results: Cytological observations led to suggestions that cell enlargement is the symbol that gametophytes had switched to the sporophyte development pathway during the early embryogenesis stage. In this stage, RNA-seq revealed 3468 up-regulated genes, including hormone signal transduction genes, hormone response genes and stress-induced genes. The reported embryogenesis-related genes BBM, HSP90 and AGL were also actively expressed during this stage. The total of 480 genes that function in protein complex binding, microtubule binding, tetrapyrrole binding, tubulin binding and other microtubule activities were continuously up-regulated during the embryo maturation stage, indicating that the cytoskeleton structure was continuously being built and maintained by the action of microtubule-binding proteins and enzyme modification during embryo development. In the shoot formation stage, 1383 genes were up-regulated, which were mainly enriched in phenylpropanoid biosynthesis, plant hormone signal transduction, phenylalanine metabolism, and starch and sucrose metabolism. The shoot formation stage might be regulated by 6 transcription factors that contained a B3 domain, 9 genes in the AP2/ERF family and 2 genes encoded WUS homologous domain proteins. Conclusions: Findings from this study offer a valuable framework for explaining the transcriptional regulatory mechanism underlying embryogenesis in cucumber ovary culture.

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Embryogenesis and plant regeneration from anther cultures of Cucumis sativus L.

Scientia Horticulturae ◽

10.1016/s0304-4238(03)00003-7 ◽

2003 ◽

Vol 98 (3) ◽

pp. 213-222 ◽

Cited By ~ 24

Author(s):

H.G. Ashok Kumar ◽

H.N. Murthy ◽

K.Y. Paek

Keyword(s):

Plant Regeneration ◽

Cucumis Sativus ◽

Cucumis Sativus L ◽

Anther Cultures

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Shoots formation from gynosinesis Cucumis sativus l.

ENGINEERING AND TECHNOLOGY ◽

10.46223/hcmcoujs.tech.en.8.1.336.2018 ◽

2020 ◽

Vol 8 (1) ◽

pp. 53-59

Author(s):

Le Thi Kim Ngoc ◽

Nguyen Tran Dong Phuong

Keyword(s):

Cucumis Sativus ◽

Callus Induction ◽

Female Flower ◽

Ovary Culture ◽

Cold Pretreatment ◽

Cucumis Sativus L ◽

Leaves And Roots ◽

Dark Conditions ◽

Haploid Plants

Haploid plants achieve through androgenesis or gynogenesis. In gynogenesis method, the ovary or ovule are used as explants induct haploid plants. Female flower one day before flowering of Cucumis sativus L. are collected. Cold pretreatment of ovaries at 4°C up to 24 hours and culture under dark conditions. Significantly enhanced callus induction response is compared with cultures under 4-week cultured on CBM medium supplemented with various concentration of TDZ 0.01-0.04 mg/L. After 4 weeks, ovaries are transferred to medium with kinetin 0.05 – 0.20 mg/L. Then, ovaries were transferred to medium supplemented with BA: IAA 3:1. Finally, green ovaries were transferred to BA 1.5 mg/L and GA3 1.5 mg/L. The results showed that ovary induction has best affected on CBM with TDZ 0.03 mg/L with 11 callus/sample. Ovaries developed on kinetin 0.1 mg/L with 7.4 callus/sample. Ovaries become green and had leaves and roots formation on BA: IAA (3 mg/L: 1 mg/L). 11 plantlets were harvested from ovary culture after 12-week culture on CBM supplemented with BA 1.5 mg/L and GA3 1.5 mg/L.

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Gynogenesis and doubled haploid production from unpollinated ovary culture of cucumber (Cucumis sativus L.)

Canadian Journal of Plant Science ◽

10.1139/cjps-2017-0112 ◽

2017 ◽

Author(s):

Atitaya Sorntip ◽

Oythip Poolsawat ◽

Chitpan Kativat ◽

Piyada Alisha Tantasawat

Keyword(s):

Cucumis Sativus ◽

Doubled Haploid ◽

Ovary Culture ◽

Cucumis Sativus L ◽

Haploid Production

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Genome-Wide Characterization of GRAS Family and Their Potential Roles in Cold Tolerance of Cucumber (Cucumis sativus L.)

International Journal of Molecular Sciences ◽

10.3390/ijms21113857 ◽

2020 ◽

Vol 21 (11) ◽

pp. 3857 ◽

Cited By ~ 1

Author(s):

Xiaohong Lu ◽

Wenqian Liu ◽

Chenggang Xiang ◽

Xiaojun Li ◽

Qing Wang ◽

...

Keyword(s):

Signal Transduction ◽

Gene Family ◽

Cold Tolerance ◽

Cucumis Sativus ◽

Expression Patterns ◽

Cold Treatment ◽

Evolutionary Tree ◽

Cucumis Sativus L ◽

Gras Family ◽

Biological Stress

Cucumber (Cucumis sativus L.) is one of the most important cucurbit vegetables but is often subjected to stress during cultivation. GRAS (gibberellic acid insensitive, repressor of GAI, and scarecrow) genes encode a family of transcriptional factors that regulate plant growth and development. In the model plant Arabidopsis thaliana, GRAS family genes function in formation of axillary meristem and root radial structure, phytohormone (gibberellin) signal transduction, light signal transduction and abiotic/biological stress. In this study, a gene family was comprehensively analyzed from the aspects of evolutionary tree, gene structure, chromosome location, evolutionary and expression pattern by means of bioinformatics; 37 GRAS gene family members have been screened from cucumber. We reconstructed an evolutionary tree based on multiple sequence alignment of the typical GRAS domain and conserved motif sequences with those of other species (A. thaliana and Solanum lycopersicum). Cucumber GRAS family was divided into 10 groups according to the classification of Arabidopsis and tomato genes. We conclude that tandem and segmental duplication have played important roles in the expansion and evolution of the cucumber GRAS (CsaGRAS) family. Expression patterns of CsaGRAS genes in different tissues and under cold treatment, combined with gene ontology annotation and interaction network analysis, revealed potentially different functions for CsaGRAS genes in response to cold tolerance, with members of the SHR, SCR and DELLA subfamilies likely playing important roles. In conclusion, this study provides valuable information and candidate genes for improving cucumber tolerance to cold stress.

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