Naslov
Degradation of chloroplast DNA during natural senescence of maple leaves

Autori
Fulgosi, Hrvoje ; Ježić, Marin ; Lepeduš, Hrvoje ; Peharec Štefanić, Petra ; Ćurković Perica, Mirna ; Cesar, Vera

Izvornik
Tree physiology (0829-318X) 32 (2012), 3; 346-354

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
deciduous plants; nucleases; nucleoids; Rubisco regulation; quantification and arrangement of plastid DNA

Sažetak
The fate of chloroplast DNA (cpDNA) during plastid development and conversion between various plastid types is still not very well understood. This is especially true for the cpDNA found in plastids of naturally senescing leaves. Here we describe changes in plastid nucleoid structure accompanied with cpDNA degradation occurring during natural senescence of free growing deciduous woody species Acer pseudoplatanus L. Natural senescence was investigated using three types of senescing leaves: green (G), yellow-green (YG) and yellow (Y). The extent of senescence was evaluated at the level of photosynthetic pigment degradation, accumulation of starch, and plastid ultrastructure. Determination of cpDNA amount was carried out by in planta visualization with 4, 6-diamidino-2-phenylindole (DAPI), by Southern hybridization, and by dot-blot using a rbcL gene probe. During natural senescence, plastid nucleoids undergo structural rearrangements accompanied by an almost complete loss of cpDNA. Furthermore, senescence-associated protein components exhibiting strong binding to a ~10 kbp rbcL-containg cpDNA fragment were identified. This interaction might be important for rbcL expression and Rubisco degradation during the course of natural senescence in trees.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Šumarstvo

POVEZANOST RADA