İskender TİRYAKİ, Hasan TUNAZ

Systemic acquired resistance: Characterization of genes associated with plant defence response

Bitkiler patojen ve böcek saldırılanlarına karşı hem lokalize hem de sistemik olan savunma mekanizmalarını harekete geçirmek suretiyle tepki gösterirler. Bunlardan bu saldırılara karşı koymak amacıyla bitkide bir bütün olarak geliştirilen "Sistemik kazanılmış direnç" (SAR), infekte olmayan dokularda patojenlerle ilgili birçok genin uyarılmasına öncülük eden farklı sinyal akış ağlarını harekete geçirmek suretiyle bir koruma sağlar. SAR'ın moleküler mekanizmasını oluşturan patojeniteyle ilgili proteinler ile bunların ekspresyonları ve bu mekanizmada görev alan salisilik asit ve jasmonat gibi sinyal moleküllerinin detayları tam anlamıyla bilinememektedir. Ancak tepkiye bağlı sinyal akış ağlarında görev alan mutant bitkilerin karakterizasyonu, kompleks bir yapıya sahip olan SAR'ın moleküler mekanizmasını küçük bileşenlerine ayırarak daha kolay anlaşılabilmesine yardımcı olmaktadır. Bu makalede SAR ile ilgili genler ile bu tepki akışında görev alan mutantların belirlenmesi tartışılacaktır.

Sonradan sistemik olarak elde edilmiş direnç: Bitki savunma cevabı ile ilgili genlerin karakterizasyonu

Plants show their defence mechanism against pathogens and insects by induction of both localized and systemic responses. Of these, systemic acquired resistance (SAR) provides a protection on the uninfected tissues by activating different signaling pathways leading to induction of several pathogen related (PR) genes upon contact with invaders. Details of the molecular mechanisms of SAR, including pathogenesis-related proteins and their expression, and the signals including salicylic acid and jasmonates are still unclear. However, characterization of mutants involved in this response pathway helps to dissect this complex mechanism of SAR. In this paper, it will be discussed genes associated with SAR and the identification of mutants involved in this response pathway.

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