Plant DNA Adds Complexity to Cell Genetics and RNA in the Orphan Crop Moringa

Jenn Hoskins
23rd May, 2024

Image Source: Natural Science News, 2024

Key Findings

The study focused on the orphan crop Moringa oleifera to understand the role of nuclear plastid DNA sequences (NUPTs) in genome evolution
NUPTs in moringa are not randomly distributed but tend to integrate into specific genomic regions, influencing genome architecture
NUPTs contribute to the formation of new genes and gene regions, increasing genetic diversity and potentially aiding adaptation

The University of Almería recently conducted a study to explore the role of nuclear plastid DNA sequences (NUPTs) in the evolution of genome architecture and function, focusing on the orphan crop Moringa oleifera (moringa)^[1]. This study addresses a significant gap in our understanding of how NUPTs contribute to genetic and phenotypic diversity, an area that has been less studied compared to transposable elements (TEs) and gene duplications. Transposable elements (TEs) are known to have a profound impact on genome and transcriptome evolution, contributing to genetic and epigenetic variation within populations and influencing adaptive evolution^[2]. Similarly, gene duplications, whether through whole-genome duplications (WGD) or small-scale duplications (SSD), have been recognized as major sources of evolutionary novelty and specialization^[3]. However, the specific contributions of NUPTs to these processes have remained largely unexplored until now. The study by the University of Almería aimed to investigate three main aspects of NUPTs in Moringa oleifera: (i) their distribution in relation to specific nuclear genomic features, (ii) their role in the emergence of new genes and gene regions, and (iii) their impact on the expression of target nuclear genes. Firstly, the researchers found that NUPTs in moringa are not randomly distributed across the genome. Instead, they exhibit biases in their localization, often integrating into specific genomic regions. This non-random distribution suggests that NUPTs may preferentially target certain areas of the genome, potentially influencing genome architecture in a manner distinct from TEs and gene duplications. Secondly, the study revealed that NUPTs contribute to the emergence of new genes and gene regions. This aligns with previous findings on the rapid origination and evolution of new genes, which play crucial roles in phenotypic evolution^[4]. By integrating into the nuclear genome, NUPTs can create novel genetic material that may be co-opted for new functions, thereby increasing genetic diversity and potentially offering adaptive advantages. Lastly, the impact of NUPTs on the expression of target nuclear genes was examined. The study found that NUPTs can influence the expression patterns of nearby genes, either enhancing or repressing their activity. This regulatory effect is reminiscent of the role of TEs in host gene regulation, where TEs can act as regulatory elements, influencing gene expression in response to environmental challenges^[2]. The stress-dependent regulation of gene expression by NUPTs could thus play a role in the adaptive responses of moringa to varying environmental conditions. In summary, the University of Almería's study on NUPTs in Moringa oleifera provides valuable insights into the evolutionary dynamics of genome architecture and function. By demonstrating the non-random distribution of NUPTs, their contribution to new gene formation, and their regulatory impact on gene expression, this study expands our understanding of the mechanisms driving genetic diversity and adaptation. These findings complement existing knowledge on TEs and gene duplications, highlighting the multifaceted nature of genome evolution and the diverse strategies organisms employ to adapt to their environments.

Genetics Biochem Plant Science

References

Main Study

1) Plastid DNA is a major source of nuclear genome complexity and of RNA genes in the orphan crop moringa

Published 22nd May, 2024

https://doi.org/10.1186/s12870-024-05158-6

Related Studies

2) The impact of transposable elements in adaptive evolution.

https://doi.org/10.1111/mec.14794

3) Evolutionary dynamics and functional specialization of plant paralogs formed by whole and small-scale genome duplications.

https://doi.org/10.1093/molbev/mss162

4) New gene evolution: little did we know.

https://doi.org/10.1146/annurev-genet-111212-133301