Cold Response Transcriptome Analysis of the Alternative Splicing Events Induced by the Cold Stress in D. catenatum.

Dendrobium catenatum Lindl is a valuable medicinal herb and gardening plant due to its ornamental value and special medical value. Low temperature is a major bottleneck restricting D. catenatum expansion towards the north, which influences the quality and yield of D. catenatum. In this study, we analysed the cold response of D. catenatum by RNA-Seq. A total of 4302 differentially expressed genes were detected under cold stress, which were mainly linked to protein kinase activity, membrane transport and the glycan biosynthesis and metabolism pathway. We also identified 4005 differential alternative events in 2319 genes significantly regulated by cold stress. Exon skipping and intron retention were the most common alternative splicing isoforms. Numerous genes were identified that differentially modulated under cold stress, including cold-induced transcription factors and splicing factors mediated by AS (alternative splicing). GO enrichment analysis found that differentially alternatively spliced genes without differential expression levels were related to RNA/mRNA processing and spliceosomes. DAS (differentially alternative splicing) genes with different expression levels were mainly enriched in protein kinase activity, plasma membrane and cellular response to stimulus. We further identified and cloned DcCBP20 in D. catenatum; we found that DcCBP20 promotes the generation of alternative splicing variants in cold-induced genes under cold stress via genetic experiments and RT-PCR. Taken together, our results identify the main cold-response pathways and alternative splicing events in D. catenatum responding to cold treatment and that DcCBP20 of D. catenatum get involved in regulating the AS and gene expression of cold-induced genes during this process. Our study will contribute to understanding the role of AS genes in regulating the cold stress response in D. catenatum.

Paramedian Thalamic Ischemic Infarction: A Retrospective Clinical Observation.

BACKGROUND: The study aimed to evaluate the clinical features in patients with bilateral and unilateral paramedian thalamic infarcts. METHODS: Twenty-one patients with paramedian thalamic infarcts were included, and their case records were reviewed. We focused on the patients' neuroimaging and neurological symptoms including the duration of coma, vertical gaze palsy, and memory impairment. The causes of bilateral and unilateral paramedian thalamic infarcts were also investigated. RESULT: Nine patients had bilateral paramedian thalamic infarcts and 12 patients had unilateral lesions. As an initial symptom, coma had occurred in 5 patients with bilateral lesions and 4 patients with unilateral lesions. Bilateral vertical gaze palsy and memory impairment were found in both groups. Most of them recovered well, except 1 patient who died due to bilateral thalamic paramedian infarction. CONCLUSIONS: Our results show that both bilateral and unilateral paramedian thalamic infarcts can cause coma, vertical gaze palsy, and memory impairment. This may promote our understanding of paramedian thalamic infarction.