Spis treści
Gotowa bibliografia na temat „Drosophila IFM”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „Drosophila IFM”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "Drosophila IFM"
1
Loya, Amy K., Sarah K. Van Houten, Bernadette M. Glasheen, and Douglas M. Swank. "Shortening deactivation: quantifying a critical component of cyclical muscle contraction." American Journal of Physiology-Cell Physiology 322, no. 4 (2022): C653—C665. http://dx.doi.org/10.1152/ajpcell.00281.2021.
Pełny tekst źródłaStreszczenie:
A muscle undergoing cyclical contractions requires fast and efficient muscle activation and relaxation to generate high power with relatively low energetic cost. To enhance activation and increase force levels during shortening, some muscle types have evolved stretch activation (SA), a delayed increased in force following rapid muscle lengthening. SA’s complementary phenomenon is shortening deactivation (SD), a delayed decrease in force following muscle shortening. SD increases muscle relaxation, which decreases resistance to subsequent muscle lengthening. Although it might be just as important to cyclical power output, SD has received less investigation than SA. To enable mechanistic investigations into SD and quantitatively compare it to SA, we developed a protocol to elicit SA and SD from Drosophila and Lethocerus indirect flight muscles (IFM) and Drosophila jump muscle. When normalized to isometric tension, Drosophila IFM exhibited a 118% SD tension decrease, Lethocerus IFM dropped by 97%, and Drosophila jump muscle decreased by 37%. The same order was found for normalized SA tension: Drosophila IFM increased by 233%, Lethocerus IFM by 76%, and Drosophila jump muscle by only 11%. SD occurred slightly earlier than SA, relative to the respective length change, for both IFMs; but SD was exceedingly earlier than SA for jump muscle. Our results suggest SA and SD evolved to enable highly efficient IFM cyclical power generation and may be caused by the same mechanism. However, jump muscle SA and SD mechanisms are likely different, and may have evolved for a role other than to increase the power output of cyclical contractions.
2
Kreuz, A. J., A. Simcox, and D. Maughan. "Alterations in flight muscle ultrastructure and function in Drosophila tropomyosin mutants." Journal of Cell Biology 135, no. 3 (1996): 673–87. http://dx.doi.org/10.1083/jcb.135.3.673.
Pełny tekst źródłaStreszczenie:
Drosophila indirect flight muscle (IFM) contains two different types of tropomyosin: a standard 284-amino acid muscle tropomyosin, Ifm-TmI, encoded by the TmI gene, and two > 400 amino acid tropomyosins, TnH-33 and TnH-34, encoded by TmII. The two IFM-specific TnH isoforms are unique tropomyosins with a COOH-terminal extension of approximately 200 residues which is hydrophobic and rich in prolines. Previous analysis of a hypomorphic TmI mutant, Ifm(3)3, demonstrated that Ifm-TmI is necessary for proper myofibrillar assembly, but no null TmI mutant or TmII mutant which affects the TnH isoforms have been reported. In the current report, we show that four flightless mutants (Warmke et al., 1989) are alleles of TmI, and characterize a deficiency which deletes both TmI and TmII. We find that haploidy of TmI causes myofibrillar disruptions and flightless behavior, but that haploidy of TmII causes neither. Single fiber mechanics demonstrates that power output is much lower in the TmI haploid line (32% of wild-type) than in the TmII haploid line (73% of wild-type). In myofibers nearly depleted of Ifm-TmI, net power output is virtually abolished (< 1% of wild-type) despite the presence of an organized fibrillar core (approximately 20% of wild-type). The results suggest Ifm-TmI (the standard tropomyosin) plays a key role in fiber structure, power production, and flight, with reduced Ifm-TmI expression producing corresponding changes of IFM structure and function. In contrast, reduced expression of the TnH isoforms has an unexpectedly mild effect on IFM structure and function.
3
Gu, Wenzhi, Qiufang Li, Meng Ding, et al. "Regular Exercise Rescues Heart Function Defects and Shortens the Lifespan of Drosophila Caused by dMnM Downregulation." International Journal of Environmental Research and Public Health 19, no. 24 (2022): 16554. http://dx.doi.org/10.3390/ijerph192416554.
Pełny tekst źródłaStreszczenie:
Although studies have shown that myomesin 2 (MYOM2) mutations can lead to hypertrophic cardiomyopathy (HCM), a common cardiovascular disease that has a serious impact on human life, the effect of MYOM2 on cardiac function and lifespan in humans is unknown. In this study, dMnM (MYOM2 homologs) knockdown in cardiomyocytes resulted in diastolic cardiac defects (diastolic dysfunction and arrhythmias) and increased cardiac oxidative stress. Furthermore, the knockdown of dMnM in indirect flight muscle (IFM) reduced climbing ability and shortened lifespan. However, regular exercise significantly ameliorated diastolic cardiac dysfunction, arrhythmias, and oxidative stress triggered by dMnM knockdown in cardiac myocytes and also reversed the reduction in climbing ability and shortening of lifespan caused by dMnM knockdown in Drosophila IFM. In conclusion, these results suggest that Drosophila cardiomyocyte dMnM knockdown leads to cardiac functional defects, while dMnM knockdown in IFM affects climbing ability and lifespan. Furthermore, regular exercise effectively upregulates cardiomyocyte dMnM expression levels and ameliorates cardiac functional defects caused by Drosophila cardiomyocyte dMnM knockdown by increasing cardiac antioxidant capacity. Importantly, regular exercise ameliorates the shortened lifespan caused by dMnM knockdown in IFM.
4
Glasheen, Bernadette M., Catherine C. Eldred, Leah C. Sullivan, et al. "Stretch activation properties of Drosophila and Lethocerus indirect flight muscle suggest similar calcium-dependent mechanisms." American Journal of Physiology-Cell Physiology 313, no. 6 (2017): C621—C631. http://dx.doi.org/10.1152/ajpcell.00110.2017.
Pełny tekst źródłaStreszczenie:
Muscle stretch activation (SA) is critical for optimal cardiac and insect indirect flight muscle (IFM) power generation. The SA mechanism has been investigated for decades with many theories proposed, but none proven. One reason for the slow progress could be that multiple SA mechanisms may have evolved in multiple species or muscle types. Laboratories studying IFM SA in the same or different species have reported differing SA functional properties which would, if true, suggest divergent mechanisms. However, these conflicting results might be due to different experimental methodologies. Thus, we directly compared SA characteristics of IFMs from two SA model systems, Drosophila and Lethocerus, using two different fiber bathing solutions. Compared with Drosophila IFM, Lethocerus IFM isometric tension is 10- or 17-fold higher and SA tension was 5- or 10-fold higher, depending on the bathing solution. However, the rate of SA tension generation was 9-fold faster for Drosophila IFM. The inverse differences between rate and tension in the two species causes maximum power output to be similar, where Drosophila power is optimized in the bathing solution that favors faster muscle kinetics and Lethocerus in the solution that favors greater tension generation. We found that isometric tension and SA tension increased with calcium concentration for both species in both solutions, reaching a maximum plateau around pCa 5.0. Our results favor a similar mechanism for both species, perhaps involving a troponin complex that does not fully calcium activate the thin filament thus leaving room for further tension generation by SA.
5
Kulke, Michael, Ciprian Neagoe, Bernhard Kolmerer, et al. "Kettin, a major source of myofibrillar stiffness in Drosophila indirect flight muscle." Journal of Cell Biology 154, no. 5 (2001): 1045–58. http://dx.doi.org/10.1083/jcb.200104016.
Pełny tekst źródłaStreszczenie:
Kettin is a high molecular mass protein of insect muscle that in the sarcomeres binds to actin and α-actinin. To investigate kettin's functional role, we combined immunolabeling experiments with mechanical and biochemical studies on indirect flight muscle (IFM) myofibrils of Drosophila melanogaster. Micrographs of stretched IFM sarcomeres labeled with kettin antibodies revealed staining of the Z-disc periphery. After extraction of the kettin-associated actin, the A-band edges were also stained. In contrast, the staining pattern of projectin, another IFM–I-band protein, was not altered by actin removal. Force measurements were performed on single IFM myofibrils to establish the passive length-tension relationship and record passive stiffness. Stiffness decreased within seconds during gelsolin incubation and to a similar degree upon kettin digestion with μ-calpain. Immunoblotting demonstrated the presence of kettin isoforms in normal Drosophila IFM myofibrils and in myofibrils from an actin-null mutant. Dotblot analysis revealed binding of COOH-terminal kettin domains to myosin. We conclude that kettin is attached not only to actin but also to the end of the thick filament. Kettin along with projectin may constitute the elastic filament system of insect IFM and determine the muscle's high stiffness necessary for stretch activation. Possibly, the two proteins modulate myofibrillar stiffness by expressing different size isoforms.
6
Zhao, Cuiping, and Douglas M. Swank. "The Drosophila indirect flight muscle myosin heavy chain isoform is insufficient to transform the jump muscle into a highly stretch-activated muscle type." American Journal of Physiology-Cell Physiology 312, no. 2 (2017): C111—C118. http://dx.doi.org/10.1152/ajpcell.00284.2016.
Pełny tekst źródłaStreszczenie:
Stretch activation (SA) is a delayed increase in force that enables high power and efficiency from a cyclically contracting muscle. SA exists in various degrees in almost all muscle types. In Drosophila, the indirect flight muscle (IFM) displays exceptionally high SA force production ( FSA), whereas the jump muscle produces only minimal FSA. We previously found that expressing an embryonic (EMB) myosin heavy chain (MHC) isoform in the jump muscle transforms it into a moderately SA muscle type and enables positive cyclical power generation. To investigate whether variation in MHC isoforms is sufficient to produce even higher FSA, we substituted the IFM MHC isoform (IFI) into the jump muscle. Surprisingly, we found that IFI only caused a 1.7-fold increase in FSA, less than half the increase previously observed with EMB, and only at a high Pi concentration, 16 mM. This IFI-induced FSA is much less than what occurs in IFM, relative to isometric tension, and did not enable positive cyclical power generation by the jump muscle. Both isometric tension and FSA of control fibers decreased with increasing Pi concentration. However, for IFI-expressing fibers, only isometric tension decreased. The rate of FSA generation was ~1.5-fold faster for IFI fibers than control fibers, and both rates were Pi dependent. We conclude that MHC isoforms can alter FSA and hence cyclical power generation but that isoforms can only endow a muscle type with moderate FSA. Highly SA muscle types, such as IFM, likely use a different or additional mechanism.
7
QIU, Feng, Anne LAKEY, Bogos AGIANIAN, et al. "Troponin C in different insect muscle types: identification of two isoforms in Lethocerus, Drosophila and Anopheles that are specific to asynchronous flight muscle in the adult insect." Biochemical Journal 371, no. 3 (2003): 811–21. http://dx.doi.org/10.1042/bj20021814.
Pełny tekst źródłaStreszczenie:
The indirect flight muscles (IFMs) of Lethocerus (giant water bug) and Drosophila (fruitfly) are asynchronous: oscillatory contractions are produced by periodic stretches in the presence of a Ca2+ concentration that does not fully activate the muscle. The troponin complex on thin filaments regulates contraction in striated muscle. The complex in IFM has subunits that are specific to this muscle type, and stretch activation may act through troponin. Lethocerus and Drosophila have an unusual isoform of the Ca2+-binding subunit of troponin, troponin C (TnC), with a single Ca2+-binding site near the C-terminus (domain IV); this isoform is only in IFMs, together with a minor isoform with an additional Ca2+-binding site in the N-terminal region (domain II). Lethocerus has another TnC isoform in leg muscle which also has two Ca2+-binding sites. Ca2+ binds more strongly to domain IV than to domain II in two-site isoforms. There are four isoforms in Drosophila and Anopheles (malarial mosquito), three of which are also in adult Lethocerus. A larval isoform has not been identified in Lethocerus. Different TnC isoforms are expressed in the embryonic, larval, pupal and adult stages of Drosophila; the expression of the two IFM isoforms is increased in the pupal stage. Immunoelectron microscopy shows the distribution of the major IFM isoform with one Ca2+-binding site is uniform along Lethocerus thin filaments. We suggest that initial activation of IFM is by Ca2+ binding to troponin with the two-site TnC, and full activation is through the action of stretch on the complex with the one-site isoform.
8
Brault, V., M. C. Reedy, U. Sauder, R. A. Kammerer, U. Aebi, and C. Schoenenberger. "Substitution of flight muscle-specific actin by human (beta)-cytoplasmic actin in the indirect flight muscle of Drosophila." Journal of Cell Science 112, no. 21 (1999): 3627–39. http://dx.doi.org/10.1242/jcs.112.21.3627.
Pełny tekst źródłaStreszczenie:
The human (beta)-cytoplasmic actin differs by only 15 amino acids from Act88F actin which is the only actin expressed in the indirect flight muscle (IFM) of Drosophila melanogaster. To test the structural and functional significance of this difference, we ectopically expressed (beta)-cytoplasmic actin in the IFM of Drosophila that lack endogenous Act88F. When expression of the heterologous actin was regulated by approximately 1.5 kb of the 5′ promoter region of the Act88F gene, little (beta)-cytoplasmic actin accumulated in the IFM of the flightless transformants. Including Act88F-specific 5′ and 3′ untranslated regions (UTRs) yielded transformants that expressed wild-type amounts of (beta)-cytoplasmic actin. Despite the assembly of (beta)-cytoplasmic actin containing thin filaments to which endogenous myosin crossbridges attached, sarcomere organization was deficient, leaving the transformants flightless. Rather than affecting primarily actin-myosin interactions, our findings suggest that the (beta)-cytoplasmic actin isoform is not competent to interact with other actin-binding proteins in the IFM that are involved in the organization of functional myofibrils.
9
Babu, Sajesh, and Nallur B. Ramachandra. "Screen for new mutations on the 2nd chromosome involved in indirect flight muscle development in Drosophila melanogaster." Genome 50, no. 4 (2007): 343–50. http://dx.doi.org/10.1139/g07-012.
Pełny tekst źródłaStreszczenie:
An extensive ethylmethanesulfonate mutagenesis of Drosophila melanogaster was undertaken to isolate the stronger alleles of 3 indirect flight-muscle mutations. We isolated 17 strong mutant lines, with nearly complete penetrance and expressivity, using direct screening under polarized light, from more than 1700 mutagenized chromosomes. On complementation, we found 11 of these 17 mutant lines to be alleles of 3 indirect flight-muscle mutations (Ifm(2)RU1, 3 noncomplementing lines; ifm(2)RU2, 6 alleles; ifm(2)RU3, 2 alleles) of the previously isolated 8 complementation groups (Ifm(2)RU1to ifm(2)RU8). In addition, we found 6 new complementation groups with strong defects in adult-muscle morphology; we named these ifm(2)RS1 to ifm(2)RS6. All mutant lines were mapped by meiotic recombination, and 5 of the 6 new complementation lines were mapped using chromosome deficiencies. ifm(2)RS1 maps to a region that harbors ifm(2)RU4 (a mutation that was isolated previously); however, theses are not alleles because each complements the other mutation, and the mutant-muscle phenotype is very different. We used direct screening under polarized light to find recessive mutations; although this method was labor intensive, it can be used to identify recessive genes involved in myogenesis, unlike screens for flightlessness or wing-position defects. This screen identifies regions on the second chromosome that harbor probable genes that are likely expressed in the mesoderm and are thought to be involved in myogenesis. This screen has generated valuable resources that will help us to understand the role of many molecular players involved in myogenesis.
10
Reedy, Mary C., Belinda Bullard, and Jim O. Vigoreaux. "Flightin Is Essential for Thick Filament Assembly and Sarcomere Stability in Drosophila Flight Muscles." Journal of Cell Biology 151, no. 7 (2000): 1483–500. http://dx.doi.org/10.1083/jcb.151.7.1483.
Pełny tekst źródłaStreszczenie:
Flightin is a multiply phosphorylated, 20-kD myofibrillar protein found in Drosophila indirect flight muscles (IFM). Previous work suggests that flightin plays an essential, as yet undefined, role in normal sarcomere structure and contractile activity. Here we show that flightin is associated with thick filaments where it is likely to interact with the myosin rod. We have created a null mutation for flightin, fln0, that results in loss of flight ability but has no effect on fecundity or viability. Electron microscopy comparing pupa and adult fln0 IFM shows that sarcomeres, and thick and thin filaments in pupal IFM, are 25–30% longer than in wild type. fln0 fibers are abnormally wavy, but sarcomere and myotendon structure in pupa are otherwise normal. Within the first 5 h of adult life and beginning of contractile activity, IFM fibers become disrupted as thick filaments and sarcomeres are variably shortened, and myofibrils are ruptured at the myotendon junction. Unusual empty pockets and granular material interrupt the filament lattice of adult fln0 sarcomeres. Site-specific cleavage of myosin heavy chain occurs during this period. That myosin is cleaved in the absence of flightin is consistent with the immunolocalization of flightin on the thick filament and biochemical and genetic evidence suggesting it is associated with the myosin rod. Our results indicate that flightin is required for the establishment of normal thick filament length during late pupal development and thick filament stability in adult after initiation of contractile activity.