How do integral membrane proteins evolve in size and complexity? Using the small multidrug-resistance protein EmrE from Escherichia coli as a model, we experimentally demonstrated that the evolution of membrane proteins composed of two homologous but oppositely oriented domains can occur in a small number of steps: An original dual-topology protein evolves, through a gene-duplication event, to ...

Microtubules are essential for polarized transport in neurons, but how their organization guides motor proteins to axons or dendrites is unclear. Because different motors recognize distinct microtubule properties, we used optical nanoscopy to examine the relationship between microtubule orientations, stability, and modifications. Nanometric tracking of motors to super-resolve microtubules and d...

During the process of prokaryotic CRISPR adaptation, a copy of a segment of foreign deoxyribonucleic acid referred to as protospacer is added to the CRISPR cassette and becomes a spacer. When a protospacer contains a neighboring target interference motif, the specific small CRISPR ribonucleic acid (crRNA) transcribed from expanded CRISPR cassette can protect a prokaryotic cell from virus infect...

graffiti as one of the social phenomenon has a very long record. however, the graffiti in modern civilization has been put forth as a media. in this article, efforts have been made to study the graffiti from the linguistic perspective. in this research, 2929 graffiti from different districts in the north, south, east, west and center of tehran have been registered and then extracted and analyze...

This paper presents experimental work on the relative naturalness of subject-oriented reflexives (herself) and pronouns (her) in English locative prepositional phrases (e.g., Michele set a glass next to her/herself). Syntactic approaches anaphor licensing have tended focus lack complementarity such constructions; however, it has long been observed that preferences between forms may depend verb ...

We show theoretically that stimulated spin-flip Raman scattering can be used to inject spin currents in doped semiconductors with spin-split bands. A pure spin current, where oppositely oriented spins move in opposite directions, can be injected in zinc blende crystals and structures. The calculated spin current should be detectable by pump-probe optical spectroscopy and anomalous Hall effect m...

Global warming is predicted to have major effects on the annual time windows during which species may successfully reproduce. At organismal level, climatic shifts engage with control mechanism for reproductive seasonality. In mammals, laboratory studies neuroendocrine emphasize photoperiod as a predictive cue, but this based restricted group of species. contrast, field-oriented comparative anal...