SIGNALING EVENTS TRIGGERS BY SULFORAPHANE IN ARABIDOPSIS THALIANA

GARCIA-MATA, C.; LAXALT AM; ARRUEBARRENA DI PALMA, ANDRES

Salta

Congreso; PABAB SAIB Congress; 2019

Sociedad Argentina de Bioquímica y Biología Molecular

Sulforaphane (SFN) isa compound encompassed within isothiocyanates molecules, a type of organosulfurcompounds. It is present almost exclusively in cruciferous plants such asbroccoli, cabbage, among others. Under no stressfull conditions, SFN is presentconjugated to a glucose molecule, being an inactive form called glucoraphanin.When cell damage occurs, by mechanical damage or herbivory, glucoraphanin actsas a substrate of myrosinase enzyme that cleaves it generating one molecule ofSFN and one free glucose.It has been shown that SFN has a role in the immuneresponse of plants. SFN participates in the resistance to pathogens throughdecrease intracellular glutathione pool affecting cellular redox state anddirectly as toxic compound against bacterial and fungal pathogens.  On the other hand, exogenous treatmentsof healthy plants with SFN, lead to priming state, a situation of"alert" in plants against possible future attacks. Mode of action ofSFN it is believed rely on its electrophile nature, that allow to react whitcellular thiols, like reduced glutathione and/or protein cysteine andhistidine.  While there isinformation about its physiological effects, as mentioned above, little isknown about the signaling events that lead to SFN final responses in plants.Inthis work we analyze the signaling responses generated by SFN treatment onArabidopsis thaliana, focus on reactive oxygen species (ROS) as well as theeffect of presence of free glucose in stoichiometry amounts.It was determinedthat SFN induces the production of ROS and this production are enhance in thepresence of glucose. Using non- metabolizable analog of this sugar, we wereable to determine effect responds to glucose catabolism and not to sugarsignaling mechanisms. In addition, we were able to determine that calciumparticipates upstream for the production of ROS, since calcium blockers andchelators reduced the ROS signal. Finally, using null mutants of A. thaliana inNADPHox D and F (RBOHD and RBOHF) we were able to determine that isoform D isresponsible for the production of ROS in response to SFN treatment.Theseresults together indicate that SFN induces the production of ROS in A. thalianathrough RBOHD activity dependent of calcium.<!-- /* Font Definitions */@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:0cm;line-height:107%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Times New Roman";mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES;}@page Section1{size:612.0pt 792.0pt;margin:72.0pt 90.0pt 72.0pt 90.0pt;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.Section1{page:Section1;}-->