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U6 small nuclear RNA (U6 snRNA), a critical spliceosome component primarily found in the nucleus, plays a vital role in RNA splicing. Our previous study, using the simian immunodeficiency virus (SIV) macaque model, revealed an increase of U6 snRNA in plasma extracellular vesicles (EVs) in acute retroviral infection. Given the limited understanding of U6 snRNA dynamics across cells and EVs, particularly in SIV infection, this research explores U6 snRNA trafficking and its association with splicing proteins in the nucleus, cytoplasm, and EVs. We observed a redistribution of U6 snRNA from the nucleus to EVs post-infection, accompanied by distinct protein profile changes and alterations in nucleic acid metabolism and spliceosome pathways. In addition, U6 machinery proteins changed in cells and EVs in a contrasting manner. The redistribution of U6 and related proteins we observed could be part of a viral strategy to redirect host splicing machinery, suggesting that U6 may have regulatory roles and be part of retroviral infection signature. 

We present an efficient, effective, and economical approach, named E3technology, for proteomics sample preparation. By immobilizing silica microparticles into the polytetrafluoroethylene matrix, we develop a robust membrane medium, which could serve as a reliable platform to generate proteomics-friendly samples in a rapid and low-cost fashion. We benchmark its performance using different formats and demonstrate them with a variety of sample types of varied complexity, quantity, and volume. Our data suggest that E3technology provides proteome-wide identification and quantitation performance equivalent or superior to many existing methods. We further propose an enhanced single-vessel approach, named E4technology, which performs on-filter in-cell digestion with minimal sample loss and high sensitivity, enabling low-input and low-cell proteomics. Lastly, we utilized the above technologies to investigate RNA-binding proteins and profile the intact bacterial cell proteome. 

Summary In maize, 24‐nt phased, secondary small interfering RNAs (phasiRNAs) are abundant in meiotic stage anthers, but their distribution and functions are not precisely known.Using laser capture microdissection, we analyzed tapetal cells, meiocytes and other somatic cells at several stages of anther development to establish the timing of 24‐PHASprecursor transcripts and the 24‐nt phasiRNA products.By integrating RNA and small RNA profiling plus single‐molecule and small RNA FISH (smFISH or sRNA‐FISH) spatial detection, we demonstrate that the tapetum is the primary site of 24‐PHASprecursor andDcl5transcripts and the resulting 24‐nt phasiRNAs. Interestingly, 24‐nt phasiRNAs accumulate in all cell types, with the highest levels in meiocytes, followed by tapetum.Our data support the conclusion that 24‐nt phasiRNAs are mobile from tapetum to meiocytes and to other somatic cells. We discuss possible roles for 24‐nt phasiRNAs in anther cell types.