Naslov
PMUs are true mobile genetic elements that can influence phytoplasma genome evolution and adaptation to plant and insect hosts

Autori
Šeruga Musić, Martina ; Toruno, Tania ; Simi, Silvia ; Nicolaisen, Mogens ; Hogenhout, Saskia A

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstract book of the scientific meeting of the COST Action FA0807 Integrated Management of Phytoplasma Epidemics in Different Crop Systems: "Current status and perspective of phytoplasma disease research and management" / Bertaccini, Assunta ; Lavina, Amparo ; Torres, Ester - , 2010, 108-108

Skup
Scientific meeting of the COST Action FA0807 Integrated Management of Phytoplasma Epidemics in Different Crop Systems: "Current status and perspective of phytoplasma disease research and management"

Mjesto i datum
Sitges, Španjolska, 01.02.2010. - 02.02.2010

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
AYWB; leafhopper; insect vector; plant pathogen; bacterium; transposition

Sažetak
Phytoplasmas replicate intracellularly in plants and insects and are dependent on both hosts for dissemination in nature. The four completely sequenced phytoplasma genomes are reduced in size. They also contain ca. 20-kb repeats, named potential mobile units (PMUs), which are characterized by the presence of ca. 21 genes encoding full-length transposases (tra5), transcription factors (sigF), DNA recombination and replication proteins (ssb, himA, dnaB, dnaG) and several predicted membrane-targeted proteins of unknown function. Here we show that PMU1 of Aster Yellows phytoplasma strain Witches’ Broom (AY-WB) exists in both linear (L-PMU1) and covalently closed circular (C-PMU1) forms. L-PMU1 is flanked by inverted 237/238-bp repeats upstream of the first gene, sigF, and downstream of the last gene, tra5. C-PMU1 contains one 238-bp repeat between sigF and tra5. This repeat is oriented in the opposite direction in C-PMU1 compared to L-PMU1. We also found that C-PMU1 copy number increases during AY-WB infection of insects compared to that of plants and this coincides with higher PMU1 gene transcript levels in insects. Thus, PMUs can exist as extrachromosomal DNAs and are therefore true mobile genomic units. These findings provide novel insights into the impact of PMUs on phytoplasma host adaptation and genome evolution.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA