miRNA and piRNA expression profiles of breeder cock testes detected by next‐generation sequencing

miRNAs are small non‐coding regulatory RNAs that play key roles in diverse biological processes. In this study, we used the Solexa sequencing technique to profile miRNAs in breeder cock testes to illustrate their functions. A total of 663 co‐expressed miRNAs and 3,180 co‐expressed piRNAs were detected in three libraries. Based on Mir‐X^? miRNA qRT‐PCR, three miRNAs representing low, medium and high expression levels according to the sequencing results were selected randomly to validate the miRNAs' expression profiles. Results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, target genes prediction of the co‐expressed miRNAs and further Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed, which revealed that some candidate miRNAs were involved in the regulation of the spermatogenesis process, spermatozoa function and testicular metabolism. In conclusion, we provided a useful resource for further elucidation of the miRNAs' regulatory role in spermatogenesis, contributing to a preliminary database for functional and molecular mechanistic studies in testicular metabolism, spermatogenesis and other testes functions.     

Fullerene pipes

Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.     

Circular polarization in star- formation regions: implications for biomolecular homochirality

Strong infrared circular polarization resulting from dust scattering in reflection nebulae in the Orion OMC-1 star-formation region has been observed. Circular polarization at shorter wavelengths might have been important in inducing chiral asymmetry in interstellar organic molecules that could be subsequently delivered to the early Earth by comets, interplanetary dust particles, or meteors. This could account for the excess of L-amino acids found in the Murchison meteorite and could explain the origin of the homochirality of biological molecules.