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1.
《Cell》2022,185(2):328-344.e26
2.
The flesh fly Sarcophaga similis show a clear photoperiodic response; they develop into adults under long days, whereas they arrest their development at the pupal stage under short days. Although the involvement of a circadian clock in photoperiodic time measurement is suggested in this species, the anatomical location of the clock neurons responsible for the time measurement has been unknown. We detected two PERIOD-immunoreactive cell clusters in the larval brain; one cluster was located at the dorsoanterior region and the other at the medial region. We further investigated their temporal changes in PERIOD-immunoreactivity and compared their patterns under different photoperiods. 相似文献
3.
Zizhen Yao Cindy T.J. van Velthoven Thuc Nghi Nguyen Jeff Goldy Adriana E. Sedeno-Cortes Fahimeh Baftizadeh Darren Bertagnolli Tamara Casper Megan Chiang Kirsten Crichton Song-Lin Ding Olivia Fong Emma Garren Alexandra Glandon Nathan W. Gouwens James Gray Lucas T. Graybuck Michael J. Hawrylycz Hongkui Zeng 《Cell》2021,184(12):3222-3241.e26
4.
Elizabeth Storer Scholl Antonella Pirone Daniel H Cox R Keith Duncan Michele H Jacob 《Channels (Austin, Tex.)》2014,8(1):62-75
Small conductance Ca2+-sensitive potassium (SK2) channels are voltage-independent, Ca2+-activated ion channels that conduct potassium cations and thereby modulate the intrinsic excitability and synaptic transmission of neurons and sensory hair cells. In the cochlea, SK2 channels are functionally coupled to the highly Ca2+ permeant α9/10-nicotinic acetylcholine receptors (nAChRs) at olivocochlear postsynaptic sites. SK2 activation leads to outer hair cell hyperpolarization and frequency-selective suppression of afferent sound transmission. These inhibitory responses are essential for normal regulation of sound sensitivity, frequency selectivity, and suppression of background noise. However, little is known about the molecular interactions of these key functional channels. Here we show that SK2 channels co-precipitate with α9/10-nAChRs and with the actin-binding protein α-actinin-1. SK2 alternative splicing, resulting in a 3 amino acid insertion in the intracellular 3′ terminus, modulates these interactions. Further, relative abundance of the SK2 splice variants changes during developmental stages of synapse maturation in both the avian cochlea and the mammalian forebrain. Using heterologous cell expression to separately study the 2 distinct isoforms, we show that the variants differ in protein interactions and surface expression levels, and that Ca2+ and Ca2+-bound calmodulin differentially regulate their protein interactions. Our findings suggest that the SK2 isoforms may be distinctly modulated by activity-induced Ca2+ influx. Alternative splicing of SK2 may serve as a novel mechanism to differentially regulate the maturation and function of olivocochlear and neuronal synapses. 相似文献
5.
6.
Dr. N. J. D. Nagelkerke A. A. M. Hart J. Oosting 《Biometrical journal. Biometrische Zeitschrift》1987,29(2):141-145
The consequences of the misspecification of a regression model are considered. For small effects of covariates a proportional consistency theorem is derived. The consistent estimation of the covariance matrix of the estimates is discussed. 相似文献
7.
Prashanth Sirigeri Jois 《Biochemical and biophysical research communications》2010,394(4):1036-1041
Bovine BSP5 belongs to the Binder of SPerm (BSP) family. BSP5 plays a role in the bovine sperm capacitation by promoting cholesterol and phospholipid efflux. The variable N-terminal part in the BSP proteins is the uncharacterized region with no known function. Full-length, N-terminal part, and individual fibronectin type II domains of bovine BSP5 were cloned, expressed and purified from Escherichia coli. His-S tagged N-terminal part showed large variation in migration on SDS-PAGE in comparison to other constructs. Using mass spectrometry it was demonstrated that the His-S-N-terminal part has the expected molecular mass (13 kDa). The recombinant N-terminal part was sensitive to E. coli endogenous proteases during purification. Denaturing purification involving boiling lysis of cells was carried out, as the protein was thermostable. The His-S-N-terminal part lacked structure as determined by CD analysis. Bioinformatics analyses confirmed that the N-terminal part of bovine BSP5 is intrinsically disordered. In addition, bioinformatics analysis indicated that rabbit BSP and multiple forms of BSP proteins of bovine and equine species possess partially or completely disordered N-terminus. The conservation of disorder at the N-terminus in BSP members belonging to different species suggests a role in biological process such as sperm capacitation and/or sperm-egg interactions. 相似文献
8.
Saburina I. N. Revishchin A. V. Aleksandrova M. A. 《Russian Journal of Developmental Biology》2002,33(1):30-36
The appearance of presumptive NO-ergic nerve cells and their differentiation in the rat neocortex were studied. For this purpose, a comparative analysis of the development and differentiation of NADPH-D-positive neurons in the neocortex transplants taken from the embryos of different ages and transplanted in the occipital cortex of adult rats and in the normally developing cerebral cortex was undertaken. The nervous tissue was stained histochemically for NADPH-D. The results we obtained suggest that no NADPH-D-containing neurons were found in the transplants from 15-day embryos, while they developed in those from 18-day embryos. Hence, precursors of NO-ergic neurons were still absent in the presumptive neocortex of 15-day embryos and appeared only on day 16–18 of embryogenesis. Expression of NADPH-D begins in them only within four to five days, but the neurons are differentiated during a relatively short period of time. Most NADPH-D-positive neurons reach their structural–functional maturity already by the end of the first week of postnatal development, while their complete maturation takes place by the end of the second week of postnatal development. 相似文献
9.
Sabina Iluta Sergiu Pasca Grigore Gafencu Ancuta Jurj Andreea Terec Patric Teodorescu Cristina Selicean Ciprian Jitaru Alexandra Preda Diana Cenariu Catalin Constantinescu Maria Iordache Bogdan Tigu Raluca Munteanu Richard Feder Delia Dima Mihnea Zdrenghea Diana Gulei Tudor-Eliade Ciuleanu Ciprian Tomuleasa 《Journal of cellular and molecular medicine》2021,25(13):6094-6102
10.
Diazocyclopentadiene (DACP) has been shown to be an effective reagent for the ethylene receptor. Treatment of mung bean sprouts or tobacco leaves with DACP in the light or in the dark inactivates much of the ethylene binding. In the light, inactivation seems to be permanent, while in the dark, the site becomes active again after the DACP diffuses away. The compound is 10 times more effective in the light than in the dark. DACP inhibits banana ripening indicating the physiological receptor is involved. It also overcomes the inhibitory effect of ethylene on mung bean seedling growth (Km = 0.09 µl/1 E) at low ethylene levels. At high ethylene levels, an apparent high ethylene level site becomes apparent (Km = 50 µl/1 E) and growth is inhibited. 相似文献