Long noncoding RNAs (lncRNAs) mediate important epigenetic regulation in a wide range of biological processes and diseases. We applied comprehensive analyses of RNA-seq and CAGE-seq (cap analysis of gene expression and sequencing) to characterize the dynamic changes in lncRNA expression in rhesus macaque (Macaca mulatta) brain in four representative age groups. We identified 18 anatomically diverse lncRNA modules and 14 mRNA modules representing spatial, age, and sex specificities. Spatiotemporal- and sex-biased changes in lncRNA expression were generally higher than those observed in mRNA expression. A negative correlation between lncRNA and mRNA expression in cerebral cortex was observed and functionally validated. Our findings offer a fresh insight into spatial-, age-, and sex-biased changes in lncRNA expression in macaque brain and suggest that the changes represent a previously unappreciated regulatory system that potentially contributes to brain development and aging.
Solanum lycopersicum and Solanum habrochaites are closely related plant species; however, their cold tolerance capacities are different. The wild species S. habrochaites is more cold tolerant than the cultivated species S. lycopersicum. The transcriptomes of S. lycopersicum and S. habrochaites leaf tissues under cold stress were studied using Illumina high-throughput RNA sequencing. The results showed that more than 200 million reads could be mapped to identify genes, microRNAs (miRNAs), and alternative splicing (AS) events to confirm the transcript abundance under cold stress. The results indicated that 21 % and 23 % of genes were differentially expressed in the cultivated and wild tomato species, respectively, and a series of changes in S. lycopersicum and S. habrochaites transcriptomes occur when plants are moved from warm to cold conditions. Moreover, the gene expression patterns for S. lycopersicum and S. habrochaites were dissimilar; however, there were some overlapping genes that were regulated by low temperature in both tomato species. An AS analysis identified 75,885 novel splice junctions among 172,910 total splice junctions, which suggested that the relative abundance of alternative intron isoforms in S. lycopersicum and S. habrochaites shifted significantly under cold stress. In addition, we identified 89 miRNA sequences that may regulate relevant target genes. Our data indicated that some miRNAs (e.g., miR159, miR319, and miR6022) play roles in the response to cold stress. Differences in gene expression, AS events, and miRNAs under cold stress may contribute to the observed differences in cold tolerance of these two tomato species.
The abundance and function of circular RNAs (circRNAs) in mammalian brain have been reported, but their alterations in the biology of brain aging remain elusive. Here, using deep RNA profiling with linear RNA digestion by RNase R we explored a comprehensive map of changes in circRNA expression in rhesus macaque (macaca mulatta) brain in two age groups from adult (10 y) to aged (20 y) periods. Total 17,050 well expressed, stable circRNAs were identified. Cluster analysis reveals that dynamic changes in circRNA expression show the spatial-, sex- and age-biased specificities. On the basis of separate profiling of the RNAs, age-related circRNAs show differential correlation to host mRNA expression. Furthermore, two voltage-dependent L- and R-type calcium channel gene-derived circCACNA2D1 and circCACNA1E negatively regulate their host mRNA expression. Our results demonstrate the power of changes in circRNA expression to reveal insights into a potentially circRNA-mediated regulatory mechanism underlying the biology of brain aging.
Plant innate immunity is capable of combating diverse and ever evolving pathogens. The plasticity of innate immunity could be boosted by RNA processing. Arabidopsis thaliana CONSTITUTIVE EXPRESSER OF PATHOGENESIS-RELATED GENES 5 (CPR5), a key negative immune regulator, is a component of the nuclear pore complex. Here we further identified CPR5 as a component of RNA processing complexes. Through genetic screening, we found that RNA splicing activator NineTeen Complex and RNA polyadenylation factor CLEAVAGE AND POLYADENYLATION SPECIFICITY FACTOR, coordinately function downstream of CPR5 to activate plant immunity. CPR5 and these two regulators form a complex that is localized in nuclear speckles, an RNA processing organelle. Intriguingly, we found that CPR5 is an RNA-binding protein belonging to the Transformer 2 (Tra2) subfamily of the serine/arginine-rich family. The RNA recognition motif of CPR5 protein binds the Tra2-targeted RNA sequence in vitro and is functionally replaceable by those of Tra2 subfamily proteins. In planta, it binds RNAs of CPR5-regulated alternatively spliced genes (ASGs) identified by RNA-seq. ARGONAUTE 1 (AGO1) is one of the ASGs and, consistent with this, the ago1 mutant suppresses the cpr5 phenotype. These findings reveal that CPR5 is an RNA-binding protein linking RNA processing with plant immunity.