2026-04-14T08:08:25Zhttps://recercat.cat/oai/requestoai:recercat.cat:20.500.12327/30422025-10-22T11:32:54Zcom_2072_4428com_2072_4427col_2072_487898
RECERCAT
author
Rodríguez-Moreno, Luis
author
González, Víctor M.
author
Benjak, Andrej
author
Martí, M. Carmen
author
Puigdomènech, Pere
author
Aranda, Miguel A.
author
Garcia-Mas, Jordi
other
Producció Vegetal
group
Genòmica i Biotecnologia
2025-10-22T11:32:54Z
2025-10-22T11:32:54Z
2011-08-20
MEC/Programa nacional de medios de transporte/CSD2007-00036/ES/Centro de Genómica Básica y de orientación Agroalimentaria/
1471-2164
http://hdl.handle.net/20.500.12327/3042
https://doi.org/10.1186/1471-2164-12-424
Background: The melon belongs to the Cucurbitaceae family, whose economic importance among vegetable
crops is second only to Solanaceae. The melon has a small genome size (454 Mb), which makes it suitable for
molecular and genetic studies. Despite similar nuclear and chloroplast genome sizes, cucurbits show great variation
when their mitochondrial genomes are compared. The melon possesses the largest plant mitochondrial genome,
as much as eight times larger than that of other cucurbits.
Results: The nucleotide sequences of the melon chloroplast and mitochondrial genomes were determined. The
chloroplast genome (156,017 bp) included 132 genes, with 98 single-copy genes dispersed between the small
(SSC) and large (LSC) single-copy regions and 17 duplicated genes in the inverted repeat regions (IRa and IRb). A
comparison of the cucumber and melon chloroplast genomes showed differences in only approximately 5% of
nucleotides, mainly due to short indels and SNPs. Additionally, 2.74 Mb of mitochondrial sequence, accounting for
95% of the estimated mitochondrial genome size, were assembled into five scaffolds and four additional
unscaffolded contigs. An 84% of the mitochondrial genome is contained in a single scaffold. The gene-coding
region accounted for 1.7% (45,926 bp) of the total sequence, including 51 protein-coding genes, 4 conserved ORFs,
3 rRNA genes and 24 tRNA genes. Despite the differences observed in the mitochondrial genome sizes of cucurbit
species, Citrullus lanatus (379 kb), Cucurbita pepo (983 kb) and Cucumis melo (2,740 kb) share 120 kb of sequence,
including the predicted protein-coding regions. Nevertheless, melon contained a high number of repetitive
sequences and a high content of DNA of nuclear origin, which represented 42% and 47% of the total sequence,
respectively.
Conclusions: Whereas the size and gene organisation of chloroplast genomes are similar among the cucurbit
species, mitochondrial genomes show a wide variety of sizes, with a non-conserved structure both in gene
number and organisation, as well as in the features of the noncoding DNA. The transfer of nuclear DNA to the
melon mitochondrial genome and the high proportion of repetitive DNA appear to explain the size of the largest
mitochondrial genome reported so far.
eng
Attribution 4.0 International
Determination of the melon chloroplast and mitochondrial genome sequences reveals that the largest reported mitochondrial genome in plants contains a significant amount of DNA having a nuclear origin
info:eu-repo/semantics/article