Mechanisms of plant response to pathogen attack

Biljke su razvile brojne mehanizme kojima prepoznaju prisutnost patogenih organizama i odgovaraju na njihove napade. Spomenuti mehanizmi prepoznavanja sastoje se od prepoznavanja molekularnih uzoraka koji potječu od mikroorganizama i patogena (MAMP odnosno PAMP), te od prepoznavanja specifičnih efektorskih molekula. U prvi dio spomenutog prepoznavanja uključeni su površinski PRR receptori, koji aktiviraju obrambeni odgovor biljaka nazvan imunosni odgovor kojeg pokreće PAMP (PAMP-triggered immunity tj. PTI), a u drugi dio unutarstanični NB-LRR receptori, koji aktiviraju obrambeni odgovor nazvan imunosni odgovor kojeg pokreće efektor (effector-triggered immunity tj. ETI). Rad opisuje organizaciju odgovora biljaka na napad patogena, s naglaskom na genskoj i molekularnoj razini odgovora, navodeći zig-zag model obrambenog odgovora biljaka kao sintezu dosadašnjih spoznaja. Ukratko se opisuju spoznaje o regulaciji ekspresije gena koji kodiraju spomenute receptorske molekule. Navodi se važnost spoznaja o obrambenom odgovoru biljaka za razvoj novih strategija za kontrolu biljnih bolesti te se daju smjernice za buduća istraživanja. Naposljetku se obrambeni odgovor biljaka uspoređuje s imunosnim sustavom u životinja, te s obzirom da biljne receptorske molekule zapravo prepoznaju modifikacije koje patogene molekule izvode na ciljnim mjestima domaćina, što veoma nalikuje razlikovanju vlastitog od promijenjenog vlastitog, te je temelj imunosnog prepoznavanja, zaključuje se da je opravdano nazvati obrambeni odgovor biljaka imunosnim odgovorom.Plants have developed many mechanisms to recognize the presence of pathogens and to respond to their attack. Mentioned recognition mechanisms consist of the identification of microbial or related pathogenic molecular patterns (PAMPs or MAMPs), and of the recognition of specific effector molecules. In the first part of the recognition surface PRR receptors are included, which activate a defense response of plants called immunity driven by PAMP (PAMP-triggered immunity i.e. PTI), and in the second part are included intracellular NB-LRR receptors, which activate a defense response called immunity driven by effector (effector-triggered immunity i.e. ETI). This paper describes the organization of the plant response to pathogen attack, focusing on genetic and molecular level of response, mentioning the zig-zag model of plant defense response as a synthesis of current knowledge. Briefly is described the understanding of the regulation of the expression of genes encoding for the defense receptor molecules. It states the importance of knowledge of the plant defense response to the development of new strategies for the control of plant diseases and is given guidance for future research. Finally, the defensive response of plants is compared with the immune system in animals, and because the plant receptor molecules actually recognize modifications that the pathogenic molecules perform at the target sites of the host, which greatly resembles the distinction between self and changed self, and is the basis of immune recognition, it is concluded that it is justified for the defense response of plants to be called immune response