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Abstract How the noncoding genome affects cellular functions is a key biological question. A particular challenge is to distinguish the effects of noncoding DNA elements from long noncoding RNAs (lncRNAs) that coincide at the same loci. Here, we identified the flowering‐associated intergenic lncRNA (FLAIL) inArabidopsisthrough early floweringflailmutants. Expression ofFLAILRNA from a different chromosomal location in combination with strand‐specific RNA knockdown characterizedFLAILas a trans‐acting RNA molecule.FLAILdirectly binds to differentially expressed target genes that control flowering via RNA–DNA interactions through conserved sequence motifs.FLAILinteracts with protein and RNA components of the spliceosome to affect target mRNA expression through co‐transcriptional alternative splicing (AS) and linked chromatin regulation. In the absence ofFLAIL, splicing defects at the direct FLAIL target flowering gene LACCASE 8 (LAC8) correlated with reduced mRNA expression. Double mutant analyses support a model whereFLAIL‐mediated splicing of LAC8 promotes its mRNA expression and represses flowering. Our study suggests lncRNAs as accessory components of the spliceosome that regulate AS and gene expression to impact organismal development.
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Mapping of neuropeptide Y expression in Octopus brains
Abstract Neuropeptide Y (NPY) is an evolutionarily conserved neurosecretory molecule implicated in a diverse complement of functions across taxa and in regulating feeding behavior and reproductive maturation inOctopus. However, little is known about the precise molecular circuitry of NPY‐mediated behaviors and physiological processes, which likely involve a complex interaction of multiple signal molecules in specific brain regions. Here, we examined the expression of NPY throughout theOctopuscentral nervous system. The sequence analysis ofOctopusNPY precursor confirmed the presence of both, signal peptide and putative active peptides, which are highly conserved across bilaterians.In situhybridization revealed distinct expression of NPY in specialized compartments, including potential “integration centers,” where visual, tactile, and other behavioral circuitries converge. These centers integrating separate circuits may maintain and modulate learning and memory or other behaviors not yet attributed to NPY‐dependent modulation inOctopus. Extrasomatic localization of NPY mRNA in the neurites of specific neuron populations in the brain suggests a potential demand for immediate translation at synapses and a crucial temporal role for NPY in these cell populations. We also documented the presence of NPY mRNA in a small cell population in the olfactory lobe, which is a component of theOctopusfeeding and reproductive control centers. However, the molecular mapping of NPY expression only partially overlapped with that produced by immunohistochemistry in previous studies. Our study provides a precise molecular map of NPY mRNA expression that can be used to design and test future hypotheses about molecular signaling in variousOctopusbehaviors.
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- Award ID(s):
- 1645219
- PAR ID:
- 10458062
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Morphology
- Volume:
- 281
- Issue:
- 7
- ISSN:
- 0362-2525
- Page Range / eLocation ID:
- p. 790-801
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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