PubMed Health⌕ Search

PubMed · 16297077

Efficient insertional mutagenesis in rice using the maize En/Spm elements.

Abstract

We have developed a novel system for insertional mutagenesis in rice (Oryza sativa) based on the maize (Zea mays) enhancer/suppressor mutator (En/Spm) element. In this system, a single T-DNA construct with Spm-transposase and the non-autonomous defective suppressor mutator (dSpm) element is used in conjunction with green fluorescent protein (GFP) and Discosoma sp. Red Fluorescence Protein (DsRed) fluorescent markers to select unlinked stable transpositions of dSpm. Using this system, we could demonstrate high frequencies of unlinked germinal transposition of dSpm in rice. Analysis of dSpm flanking sequences from 353 stable insertion lines revealed that the dSpm insertions appear to be widely distributed on rice chromosomes with a preference for genic regions (70%). The dSpm insertions appear to differ from Activator-Dissociation (Ac-Ds) elements in genomic distribution and exhibit a greater fraction of unlinked transpositions when compared with Ds elements. The results obtained in this study demonstrate that the maize En/Spm element can be used as an effective tool for functional genomics in rice and can complement efforts using other insertional mutagens. Further, the efficacy of the non-invasive fluorescence-based selection system is promising for its application to other crops.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chellian Santhosh Kumar, Rod A Wing, Venkatesan Sundaresan. 2005. Efficient insertional mutagenesis in rice using the maize En/Spm elements.. https://doi.org/10.1111/j.1365-313x.2005.02570.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Chromosome-level genome assembly of Manglietia pachyphylla.

Manglietia pachyphylla, an endangered evergreen tree within the Magnoliaceae family, is renowned for its exceptional ornamental value in landscape horticulture. Despite its classification as a Category II nationally protected plant species in China, the genetic basis of its adaptive traits and conservation priorities remains poorly understood. To address this, we present the first chromosome-scale genome assembly of M. pachyphylla utilizing an integrated approach combining PacBio HiFi long-read and Hi-C chromosome conformation capture sequencing technologies. The assembled genome spans 2.15 Gb (contig N50 = 43.57 Mb), exhibiting a heterozygosity rate of 0.78% and repeat content of 78.64%, predominantly comprising long terminal repeat (LTR) retrotransposons (52.86%). Hi-C scaffolding anchored 99.57% of the assembly to 19 pseudochromosomes, achieving a BUSCO completeness score of 96.4%. Annotation revealed 42,505 putative protein-coding genes, with 84.46% of predicted genes were functionally annotated. Phylogenomic analysis positioned M. pachyphylla and Oyama sieboldii clustered together in a well-supported group. This high-contiguity genome assembly enables future investigations into adaptive evolution, functional genomics, and evidence-based conservation strategies for this endangered species.

Chromosomes, Plant↗

Chromosome-level genome assembly of Elaeocarpus petiolatus (Elaeocarpaceae).

Elaeocarpus petiolatus is an ecologically and economically important species in tropical and subtropical forests. Despite its significance, the lack of genomic resources has hindered research on the genetic diversity and adaptive traits of E. petiolatus. To address this gap, we present a comprehensive chromosome-level genome assembly of E. petiolatus generated using advanced PacBio high-fidelity (HiFi) long-read sequencing and Hi-C technology. The assembly spans 322.45 Mb, with a scaffold N50 of 20.58 Mb, indicating that 37.11% of the genome is composed of repetitive elements. We identified 25,295 protein-coding genes, of which 96.74% were functionally annotated. This high-quality genome provides a critical resource for understanding the genetic mechanisms underlying environmental adaptability and biosynthesis of bioactive compounds in E. petiolatus, thereby supporting conservation efforts and sustainable forest management. The assembled genome and associated sequencing data are publicly available, facilitating further evolutionary and functional studies on the Elaeocarpaceae family.

Chromosomes, Plant↗

Cytogenetics and genomics analysis of cold-hardy perennial wheatgrass: insights into agronomic performance, chromosome composition, and gene expression.

Intermedium wheatgrass (Thinopyrum intermedium), a perennial species with extensive root systems and high tolerance to cold, drought, and salinity, is a valuable genetic resource for the development of perennial crops. Over a decade-long selection process, two cold-hardy perennial wheatgrass lines were developed by crossing wheat-Thinopyrum partial amphiploids with Th. intermedium. These lines inherited key traits from Th. intermedium, including plant stature, spike morphology, and postharvest regrowth. Transcriptome-based single-nucleotide polymorphism tracing and sequential multicolor genomic in situ hybridization analyses revealed variations in the chromosome compositions of the perennial wheatgrass lines. The introgression of wheat chromosomes enhanced grain weight and size, while preserving the cold-hardy, perennial characteristics of the wheatgrass lines compared to Th. intermedium. Genome-wide gene expression was generally suppressed in the wheatgrass lines relative to Th. intermedium, particularly in conserved genes. This suppression was especially pronounced in genes involved in cell division and DNA repair pathways. In contrast, genes associated with cold tolerance and the water stress response were upregulated. We identified eight cold-tolerance genes in the Th. intermedium chromosomes and validated three of them, Thint.J05G452200, Thint.J05G452300, and Thint.V05G408900, using qRT-PCR. These genes encode proteins associated with cold tolerance and are potential candidates for further functional validation. Additionally, three chromosomes from homoeologous group 6 were introgressed, carrying six genes potentially associated with superior grain traits. Among them, TraesCS6D02G287800, which encodes a specific protein, exhibited high expression levels in both wheatgrass lines, suggesting its critical role in enhancing grain traits. Our results indicate that the suppression of grass gene expression, likely due to the introgression of wheat chromosomes and the upregulation of pathways related to cold tolerance and overwintering ability, contributes to the adaptive features of the wheatgrass lines. This study provides a genomic foundation for understanding gene expression regulation in distant hybrid progeny and offers valuable insights for designing new breeding strategies for perennial wheat or wheatgrass.

Chromosomes, Plant↗