http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
( Dennis K Bideshi ),( Greer Waldrop ),( Maria Teresa Fernandez Luna ),( Mercedes Diaz Mendoza ),( Margaret C Wirth ),( Jeffrey J Johnson ),( Hyun Woo Park ),( Brian A Federici ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.8
The Cyt1Aa protein of Bacillus thuringiensis susbp. israelensis elaborates demonstrable toxicity to mosquito larvae, but more importantly, it enhances the larvicidal activity of this species Cry proteins (Cry11Aa, Cry4Aa, and Cry4Ba) and delays the phenotypic expression of resistance to these that has evolved in Culex quinquefasciatus. It is also known that Cyt1Aa, which is highly lipophilic, synergizes Cry11Aa by functioning as a surrogate membrane-bound receptor for the latter protein. Little is known, however, about whether Cyt1Aa can interact similarly with other Cry proteins not primarily mosquitocidal; for example, Cry2Aa, which is active against lepidopteran larvae, but essentially inactive or has very low toxicity to mosquito larvae. Here we demonstrate by ligand binding and enzyme-linked immunosorbent assays that Cyt1Aa and Cry2Aa form intermolecular complexes in vitro, and in addition show that Cyt1Aa facilitates binding of Cry2Aa throughout the midgut of C. quinquefasciatus larvae. As Cry2Aa and Cry11Aa share structural similarity in domain II, the interaction between Cyt1Aa and Cry2Aa could be a result of a similar mechanism previously proposed for Cry11Aa and Cyt1Aa. Finally, despite the observed interaction between Cry2Aa and Cyt1Aa, only a 2-fold enhancement in toxicity resulted against C. quinquefasciatus. Regardless, our results suggest that Cry2Aa could be a useful component of mosquitocidal endotoxin complements being developed for recombinant strains of B. thuringiensis subsp. israelensis and B. sphaericus aimed at improving the efficacy of commercial products and avoiding resistance.
Loss-of-function mutations in sodium channel Na<sub>v</sub>1.7 cause anosmia
Weiss, Jan,Pyrski, Martina,Jacobi, Eric,Bufe, Bernd,Willnecker, Vivienne,Schick, Bernhard,Zizzari, Philippe,Gossage, Samuel J.,Greer, Charles A.,Leinders-Zufall, Trese,Woods, C. Geoffrey,Wood, John N. Nature Publishing Group, a division of Macmillan P 2011 Nature Vol.472 No.7342
Loss of function of the gene SCN9A, encoding the voltage-gated sodium channel Na<SUB>v</SUB>1.7, causes a congenital inability to experience pain in humans. Here we show that Na<SUB>v</SUB>1.7 is not only necessary for pain sensation but is also an essential requirement for odour perception in both mice and humans. We examined human patients with loss-of-function mutations in SCN9A and show that they are unable to sense odours. To establish the essential role of Na<SUB>v</SUB>1.7 in odour perception, we generated conditional null mice in which Na<SUB>v</SUB>1.7 was removed from all olfactory sensory neurons. In the absence of Na<SUB>v</SUB>1.7, these neurons still produce odour-evoked action potentials but fail to initiate synaptic signalling from their axon terminals at the first synapse in the olfactory system. The mutant mice no longer display vital, odour-guided behaviours such as innate odour recognition and avoidance, short-term odour learning, and maternal pup retrieval. Our study creates a mouse model of congenital general anosmia and provides new strategies to explore the genetic basis of the human sense of smell.