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O'Rourke, J.

Publications and source records attributed to O'Rourke, J..

3 recordsLinked to original sources

High Temperature and Microbiome Conditions Affect Gene Expression in Soybean

Heat stress is increasingly a problem in global agriculture production, both in increasing occurrences and extended durations. Understanding the molecular mechanisms of the soybean heat stress response is essential for breeding heat tolerant soybeans. Plant associated microbiomes are known to mitigate adverse effects from abiotic stress. Soybean heat stress studies have primarily focused on response to short periods of stress, and how soybean responds on a transcriptional level to a soil microbiome is poorly understood. We hypothesize a soil microbiome may help soybean survive long-term heat stress exposure. We used RNA-seq to measure the transcriptional responses in four soybean exposed to two temperature regimes and grown in two soil microbiome conditions. We identified unique responses to temperature based on the soil microbiome conditions and to the different genotypes, with fewer changes across genotypes in response to a soil microbiome. Our findings provide insights on the interaction of soil microbiome with heat stress response in soybean and identify gene targets to further study the soybean heat stress tolerance with applications to develop improved varieties.

plant biology↗

Transcriptional signatures associated with waterlogging stress responses and aerenchyma formation in barley root tissue

The negative impact of soil waterlogging on crop production is expected to increase due higher frequencies of extreme rainfall events arising from climate change. Consequently, understanding the molecular mechanisms that enable plants to mitigate waterlogging stress is critical for breeding programmes, particularly in the case of waterlogging-susceptible crop species, such as barley (Hordeum vulgare). Aerenchyma formation is a key morphological adaptation allowing plants to cope with waterlogging stress and hypoxic conditions, however, the genetic regulation of its development in barley remains largely unresolved. In this study, two barley cultivars with contrasting waterlogging tolerance (Franklin and Yerong) were subjected to waterlogging stress, followed by analysis of phenotypic traits including root aerenchyma formation, and transcriptomic profiling of root tissue samples. Differential expression analyses identified genes transcriptionally responsive to 24 and 72 h of waterlogging in both cultivars, and highlighted metabolic adaptations, regulation of ROS signalling and management of stress responses as key elements of the waterlogging response. The results revealed large intra-individual variations in root aerenchyma formation, and these variations were exploited to isolate 81 candidate aerenchyma-associated genes from the generated RNA-seq datasets. Network analyses suggest the involvement of the DNA damage response gene, DRT100 and cell wall modifying genes, XHT16 and XHT15 as regulatory hub genes in aerenchyma formation. Collectively, the generated data provide insights into transcriptional signatures associated with the barley root responses to waterlogging and aerenchyma formation, informing our understanding of strategies that plants employ to cope with the negative impacts of heavy rainfall.

plant biology↗

The microprotein Minion controls cell fusion and muscle formation

Although recent evidence has pointed to the existence of small open reading frame (smORF)-encoded microproteins in mammals, the functional repertoire of this microproteome remains to be determined1. In skeletal muscle, proper development requires fusion of mononuclear progenitors to form multinucleated myotubes, a critical but poorly understood process2,3. Here we report the identification of a small ORF encoding an essential skeletal muscle specific microprotein we term Minion (microprotein inducer of fusion). Myogenic progenitors lacking Minion differentiate normally but fail to form syncytial myotubes, and Minion-deficient mice die perinatally with marked reduction in fused muscle fibers. This fusogenic activity is conserved to the human Minion ortholog, previously annotated as a long noncoding RNA. Loss-of-function studies demonstrate that Minion is the factor providing muscle specific fusogenic function for the transmembrane protein Myomaker4. Remarkably, we demonstrate that co-expression of Minion and Myomaker is sufficient to induce rapid cytoskeletal rearrangement and homogeneous cellular fusion, even in non-muscle cells. These findings establish Minion as a novel microprotein required for muscle development, and define a two-component program for the induction of mammalian cell fusion, enabling both research and translational applications. Importantly, these data also significantly expand the known functions of smORF-encoded microproteins, an under-explored source of proteomic diversity.

cell biology↗