Free-Hand Intracerebroventricular Injections in Mice.

The investigation of neuroendocrine systems often requires the delivery of drugs, viruses, or other experimental agents directly into the brains of mice. An intracerebroventricular (ICV) injection allows the widespread delivery of the experimental agent throughout the brain (particularly in the structures near the ventricles). Here, methods for making free-hand ICV injections in adult mice are described. By using visual and tactile landmarks on the heads of mice, injections into the lateral ventricles can be made rapidly and reliably. The injections are made with a glass syringe held in the experimenter's hand and placed at approximate distances from the landmarks. Thus, this technique does not require a stereotaxic frame. Furthermore, this technique requires only brief isoflurane anesthesia, which permits the subsequent assessment of mouse behavior and/or physiology in awake, freely behaving mice. Free-hand ICV injection is a powerful tool for the efficient delivery of experimental agents into the brains of living mice and can be combined with other techniques such as frequent blood sampling, neural circuit manipulation, or in vivo recording to investigate neuroendocrine processes.

A chromosome-scale reference of Chenopodium watsonii helps elucidate relationships within the North American A-genome Chenopodium species and with quinoa.

Quinoa (Chenopodium quinoa), an Andean pseudocereal, attained global popularity beginning in the early 2000s due to its protein quality, glycemic index, and high fiber, vitamin, and mineral contents. Pitseed goosefoot (Chenopodium berlandieri), quinoa's North American free-living sister species, grows on disturbed and sandy substrates across the North America, including saline coastal sands, southwestern deserts, subtropical highlands, the Great Plains, and boreal forests. Together with South American avian goosefoot (Chenopodium hircinum) they comprise the American tetraploid goosefoot complex (ATGC). Superimposed on pitseed goosefoot's North American range are approximately 35 AA diploids, most of which are adapted to a diversity of niche environments. We chose to assemble a reference genome for Sonoran A-genome Chenopodium watsonii due to fruit morphological and high (>99.3%) preliminary sequence-match similarities with quinoa, along with its well-established taxonomic status. The genome was assembled into 1377 scaffolds spanning 547.76 Mb (N50 = 55.14 Mb, L50 = 5), with 94% comprised in nine chromosome-scale scaffolds and 93.9% Benchmarking Universal Single-Copy Orthologs genes identified as single copy and 3.4% as duplicated. A high degree of synteny, with minor and mostly telomeric rearrangements, was found when comparing this taxon with the previously reported genome of South American C. pallidicaule and the A-subgenome chromosomes of C. quinoa. Phylogenetic analysis was performed using 10,588 single-nucleotide polymorphisms generated by resequencing a panel of 41 New World AA diploid accessions and the Eurasian H-genome diploid Chenopodium vulvaria, along with three AABB tetraploids previously sequenced. Phylogenetic analysis of these 32 taxa positioned the psammophyte Chenopodium subglabrum on the branch containing A-genome sequences from the ATGC. We also present evidence for long-range dispersal of Chenopodium diploids between North and South America.

The conserved alternative splicing factor caper regulates neuromuscular phenotypes during development and aging.

RNA-binding proteins play an important role in the regulation of post-transcriptional gene expression throughout the nervous system. This is underscored by the prevalence of mutations in genes encoding RNA splicing factors and other RNA-binding proteins in a number of neurodegenerative and neurodevelopmental disorders. The highly conserved alternative splicing factor Caper is widely expressed throughout the developing embryo and functions in the development of various sensory neural subtypes in the Drosophila peripheral nervous system. Here we find that caper dysfunction leads to aberrant neuromuscular junction morphogenesis, as well as aberrant locomotor behavior during larval and adult stages. Despite its widespread expression, our results indicate that caper function is required to a greater extent within the nervous system, as opposed to muscle, for neuromuscular junction development and for the regulation of adult locomotor behavior. Moreover, we find that Caper interacts with the RNA-binding protein Fmrp to regulate adult locomotor behavior. Finally, we show that caper dysfunction leads to various phenotypes that have both a sex and age bias, both of which are commonly seen in neurodegenerative disorders in humans.

Rhenium-catalyzed aromatic propargylation.

A mild aromatic propargylation reaction, employing an air- and moisture-tolerant rhenium-oxo complex ((dppm)ReOCl(3)) as a catalyst and a propargyl alcohol as the electrophile, is described. The reaction tolerates a broad range of functional groups and regioselectively affords propargylic arenas without formation of the isomeric allenyl adducts. The potential of this rhenium(V)-catalyzed reaction is exemplified by application of the propargylation to the synthesis of O-methyldetrol, mimosifoliol, and beta-apopicropodophyllin. [reaction: see text]