• Aucun résultat trouvé

Regulation of the expression of ethylene biosynthesis genes in Hevea brasiliensis shoots


Academic year: 2021

Partager "Regulation of the expression of ethylene biosynthesis genes in Hevea brasiliensis shoots"

En savoir plus ( Page)

Texte intégral


IRRDB Workshop on Hevea Genome and Transcriptome 2009 3-5 June 2009


Regulation of the expression of ethylene biosynthesis genes in

Hevea brasiliensis shoots

Montoro P.


, Rio M., Leclercq J., G. Oliver, Sabau X.

UMR-DAP, CIRAD, TA A96/03, 34398 Montpellier, France


Corresponding author (e-mail: pascal.montoro@cirad.fr)


Ethephon, an ethylene generator, is applied to the bark of rubber trees to increase natural rubber production by stimulating both latex flow and regeneration. A good command of both ethephon concentration and its frequency of application is required to avoid an oxidative burst into latex cells resulting in tapping panel dryness (TPD) and a loss of production. Although a little is known about the molecular response to ethylene stimulation further studies on ethylene biosynthesis and its regulation were needed to gain a better understanding of the mechanisms involved in latex production.

The ethylene biosynthesis pathway is well characterised in many plant species. S-adenosyl-methionin (SAM) is produced from the methionin (Met) by the enzyme SAM synthase. Then, SAM is converted in 1-aminocyclopropane-1-carboxylic acid (ACC) by the ACC synthase (ACS) (Kende, 1993; Yang & Hoffman, 1984). ACC is convertedto ethylene by the enzyme ACC oxidase, the production of whichis also highly regulated. These three enzymes are encoded by a multigene familyand their expression regulated differentially by various developmental, environmental and hormonal signals (Barry et

al., 2000; Ge et al., 2000; Hacham et al., 2007; Llop-Tous et al., 2000)

Several genes involved in the ethylene biosynthesis were previously isolated in rubber tree from cDNA library screening or PCR amplification of conserved regions using degenerated primers then RACE extension technology (Kuswanhadi, 2006). A differential gene expression was observed during plant development (Kuswanhadi et al., 2005) and a kinetic in response to ethephon, ethylene and wounding in 3-month-old budded plants (Kuswanhadi et al., 2006). In this study, we have monitored the expression of eight genes encoding four enzymes (SAMS, ACS, ACO and βCAS) by real-time RT-PCR. These expression levels in bark tissues of budded plant 3-month-old flushes were compared from three Hevea clones with contrasting metabolism.

The variation in gene expression depends on the clones and the genes. The accumulation of SAMS transcripts is dramatically increased in line with the decrease of the clone metabolism. In addition, this gene is induced during the daytime. ACS genes are poorly expressed in any clones. By contrast, ACO1 transcripts are accumulated in clone PB 260 and its gene is down-regulated during the daytime. ACO2 gene is more expressed at time 8 am in PB 217 than in other clones, and then induced during daytime. ACO3 gene is expressed at a very high level in PB 260. βCAS transcripts are accumulated in all clones and induced by the daytime in RRM 600 and PB 260.


IRRDB Workshop on Hevea Genome and Transcriptome 2009


SAMS, ACS1, ACS-F3, ACS-F10 and ACO2 transcripts were dramatically accumulated

after wounding treatment in the three studied clones. Interestingly, ACS1 gene is the most up-regulated one. An overnight pre-treatment with an inhibitor of the ethylene action, the 1-MCP, partially blocked the induction of this gene by wounding in clones PB 217 and RRIM 600.

The expression of SAMS, ACO1, ACO2, ACO3 and βCAS genes was very slightly

modified upon ethylene treatment whatever the clone. By contrast, ACS gene is regulated by ethylene. Transcripts were accumulated for ACS1 and ACS-F10 in clone RRIM 600,

ACS-F3 in clones PB 217 and RRIM 600,

These data suggest that the studied clones respond more actively to wounding than to the ethylene treatment. The low expression level of the SAMS gene recorded in clone PB 260 might be a limiting factor for the ethylene production. Expression of ACS genes is also very low and transient in all studied clones. ACS is the first committed and generally rate-limiting step in ethylene biosynthesis (Kende, 1993; Zarembinski & Theologis, 1994). This inhibition and the early induction of ACS1 might suggest that wounding effect uses the ethylene signalling pathway through the control of the degradation of the ACS by the proteasome dependent pathway. The differential expression of genes between studied clones is a source of variability for genetic studies using Single Nucleotide Polymorphism for instance. The production of cyanide is concomitant to ethylene. The release of toxic HCN from damaged plant tissues is generally considered as a constitutive plant defence. The expression of βCAS gene is not a limiting factor for

cyanide detoxification.

Acknowledgement: This work was supported by the Institut Français pour le Caoutchouc. References

Barry, C. S., Llop-Tous, M. I. & Grierson, D. (2000). The regulation of

1-aminocyclopropane-1-carboxylic acid synthase gene expression during the transition from system-1 to system-2 ethylene synthesis in tomato. Plant Physiol 123, 979-986.

Ge, L., Liu, J. Z., Wong, W. S., Hsiao, W. L. W., Chong, K., Xu, Z. K., Yang, S. F., Kung, S. D. & Li, N. (2000). Identification of a novel multiple environmental factor-responsive

1-aminocyclopropane-1-carboxylate synthase gene, NT-ACS2, from tobacco. Plant Cell Env 23, 1169-1182.

Hacham, Y., Song, L., Schuster, G. & Amir, R. (2007). Lysine enhances methionine content by

modulating the expression of S-adenosylmethionine synthase. Plant J 51, 850-861.

Kende, H. (1993). Ethylene biosynthesis. Ann Rev Plant Physiol Plant Mol Biol 44, 283-307.

Kuswanhadi, Leclercq, J., Sumarmadji, Rio, M., Alemanno, L. & Montoro, P. (2005).Isolation and

characterization of three members of the multigenic family encoding ACC oxidase from H. brasiliensis during plant development. In International Workshop on Tapping Panel Dryness of Rubber. Cochin, Kerala, India.

Kuswanhadi (2006).Isolement et caractérisation des gènes ACS et ACO impliqués dans la biosynthèse de

l'éthylène chez Hevea brasiliensis. In Académie de Montpellier, pp. 146: Université Montpellier II, Sciences et techniques du Languedoc.

Kuswanhadi, Leclercq, J., Sumarmadji, Rio, M. & Montoro, P. (2006). Isolation and expression of

ACO genes in Hevea brasiliensis. In Advances in Plant Ethylene Research. Pisa, Italy.

Llop-Tous, I., Barry, C. S. & Grierson, D. (2000). Regulation of ethylene biosynthesis in response to

pollination in tomato flowers. Plant Physiol 123, 971-978.

Yang, S. F. & Hoffman, N. E. (1984). Ethylene biosynthesis and its regulation in higher plants. Ann Rev


IRRDB Workshop on Hevea Genome and Transcriptome 2009


Zarembinski, T. I. & Theologis, A. (1994). Ethylene biosynthesis and action: a case of conservation.


Documents relatifs

The lack of ApcD and ApcF affects differently energy transfer and state transitions in different cyanobacteria strains, indicating that conclusions based on

Glyphosate and AMPA passive sampling in freshwater using a microporous polyethylene diffusion sampler7. Vincent Fauvelle, Natalia Montero, Jochen Mueller, Andrew Banks,

Within Xanthomonas, sequences from the clade of CbsA homologs found in both vascular and nonvascular pathogens are located in type 3 neighborhoods, while sequences from the clade

Transcriptional and post-transcriptional regulation of genes involved in the production and scavenging of reactive oxygen species and antioxidant biosynthesis in Hevea

This work described the successful establishment of transgenic lines carrying the two transcription factors HbERF-IXc4 and HbERF- IXc5 under the control of 35S CaMV or

tanaman karet. Sebagaimana diketahui, efek genotip pada klon tanaman karet dapat memberikan ekspresi yang berbeda dari gen yang sama. Perbedaan ekspresi tersebut

Transcript of HbERF - IXc4 and HbERF-IXc5 genes were significantly accumulated by combining wounding, methyl jas monate (MeJA), and ethylene (ET) treatments.. Crosstalk

Expression profiles of the HbMIR398a, HbMIR398b and HbMIR398c genes and their chloroplastic HbCuZnSOD target by real time-PCR in leaves, bark and roots of one-year-old

Ethylene biosynthesis genes are transcriptionally induced in peel tissue by ripening (i.e. an increase in their mRNA accumulation in the median zone), MaACS1 and MaACO1 being the

Comparison Cp value of callus with various embryogenic capacities grown on embryogenesis induction medium (ENT) and somatic embryogenesis expression medium (EXP) {Calli are from

1,2   and Mbéguié‐A‐Mbéguié D 1,2 *    1 CIRAD, UMR QUALISUD, F‐ 97130 Capesterre‐Belle‐Eau, Guadeloupe France 

ƒ Physiological and molecular mechanism underlying finger drop process involved ethylene biosynthesis elements including, developmental- and ripening-induced gene (MaACO1),

T r ansgenic Hevea brasiliensis plants overexpressing an ethylene mutant receptor etr l -1 f rom Arabidopsis thaliana were regenerated. Hainan, China pascal.montoro

tress in latex cells and usually associated with endogenous ethylene production.. ln

On the kinetics level, 4 of the 25 genes were up-regulated among the different time; on the MeJA response level, 8 genes of them were up regulated in the response to MeJA

Depuis la réapparition du tramway dans l’agglomération parisienne (ligne T1 entre Saint-Denis et Bobigny en 1992), s’est tissé un réseau incomplet de neuf lignes (105

Les variables de l’optimisation sont les variables du modèle de dimensionnement. L’objectif est de maximiser le rendement de l’entrainement en imposant des contraintes sur

The change of Ag NPs size after the growth of the top dielectric layer is also detected by optical transmittance when silver was deposited with the highest power density on the

These control strategies will be compared for 3-level FC, and 3-level NPC topologies and their effect on the converter weight and performances will be studied to find the

En conclusion de ce Chapitre 9, on peut dire que le concept de SE a contribué à la compréhension de notre question de thèse en éclairant les divergences

Gene expression analysis by reverse-Northern carried out on clones identified in the ET - and ET + libraries after 24h of ethylene treatment.. Ethylene was applied as a gas at 1ppm

Some examples of in situ hybridization use are described for Hevea gene expression in somatic plantlets and shoot bark: the uidA gene in callus and transgenic somatic plantlets,

In phylogenetic analysis, although MaEIL1, 3 and 4 belong to the cluster consisting of EIN3 and EIN3-like proteins known to be involved in ethylene transduction pathway,