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991.
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A human gene similar to Drosophila melanogaster peanut maps to the DiGeorge syndrome region of 22q11
Judith M. McKie Helen F. Sutherland Emma Harvey Ung-Jin Kim P. J. Scambler 《Human genetics》1997,101(1):6-12
A Drosophila-related expressed sequence tag (DRES) with sequence similarity to the peanut gene has previously been localized to human chromosome 22q11. We have isolated the cDNA corresponding to this DRES and show that it is a novel member of the family of septin genes, which encode proteins with GTPase activity thought to interact during cytokinesis. The predicted protein has P-loop nucleotide binding and GTPase motifs. The gene, which we call PNUTL1, maps to the region of 22q11.2 frequently deleted in DiGeorge and velo-cardio-facial syndromes and is particularly highly expressed in the brain. The mouse homologue, Pnutl1, maps to MMU16 adding to the growing number of genes from the DiGeorge syndrome region that map to this chromosome. 相似文献
994.
Ralf Heinrich N. Elsner 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,180(3):257-269
Stridulation in many gomphocerine grasshoppers is characterized by specific phase shifts between the two hindlegs as well
as different movement patterns produced by the left and the right leg. The underlying neuronal excitation patterns are generated
by networks on either side of the metathoracic ganglion. The role of the intraganglionic commissures in right-left coordination
and the production of differing movement patterns was investigated by transecting the metathoracic ganglion mediosagittally
in Omocestus viridulus, Chorthippus biguttulus and Chorthippus mollis. In all three species, after this operation both hindlegs produced the same pattern and no longer different movements. The effects of transection on coordination differed: rapid movement rhythms, like
those typical of Ch. biguttulus and the vibratory parts of the song of Ch. mollis, on the two sides drifted with respect to one another. In contrast, the slow rhythms characteristic of O. viridulus and the song subunits of Ch. mollis were completely synchronized. It is inferred that in intact animals the pathways for coordination of the rapid stridulatory
rhythms are exclusively intraganglionic, whereas the phase relations of the slow rhythms are additionally influenced by way
of anterior right-left connections, perhaps within the suboesophageal ganglion.
Accepted: 15 October 1996 相似文献
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Chun Y. Gao Peggy S. Zelenka 《BioEssays : news and reviews in molecular, cellular and developmental biology》1997,19(4):307-315
Cyclin-dependent kinases and their regulatory subunits, the cyclins, are known to regulate progression through the cell cycle. Yet these same proteins are often expressed in non-cycling, differentiated cells. This review surveys the available information about cyclins and cyclin-dependent kinases in differentiated cells and explores the possibility that these proteins may have important functions that are independent of cell cycle regulation. 相似文献
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The NADPH-dependent reduction of some photosynthetic electron carriers in the dark, and the reduction of NADP+ associated
with the glycolytic sequence and the oxidative pentose phosphate pathway in chloroplasts are reviewed. The postulated pathways
of electron transports sensitive and insensitive to antimycin A are also evaluated. It is proposed that the electron flow,
predominantly through cytochrome bf complex, may be also involved in the pathway of NADPH-dependent and antimycin A-insensitive back electron transport. An information
on the chlororespiration in higher plants is also included.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
1000.