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[
Worm Breeder's Gazette,
1997]
In this investigation nematodes C. elegans lived in liquid me- dium with E. coli and water solution of royal jelly extract in concentration 1:100 000 000 in order to study its effect on longevity of these worms in comparison with control, where ne- matodes lived without this extract. Three adult animals (3 - 5 days old) were kept in microtitre wells containing 0,75 ml of liquid medium (with E. coli and without royal jelly extract) during 4 hours, then they were discarded and newborn larvae we- re transferred in next wells (with royal jelly extract in any concentration) every day (one worm in one well). This investi- gation was carried out in room temperature and in the dark- ness. The obtained results were as follows (mean and standard error): Control group Experimental group Longevity (in days) Mean 17,19 +/- 1,03 16,31 +/- 1,08 Maximal 29 30 Minimal 8 7 Number of animals 36 35 Conclusion: The water solution of royal jelly extract has no effect on C. elegans longevity.
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[
Worm Breeder's Gazette,
1996]
The purpose of this study was the effect of different concentrations of royal jelly extract on nematode life span. In this experiment royal jelly extract was used in the form of "Apilactosa" (produced by "Fertane", Moscow, Nagatinskaya str., 1) in following dilutions 1:10*3, 1:10*4, 1:10*5, 1:10*6 , 1:10*7 , 1:10*8 , 1:10*9 and 1:10*10. Three adult animals (3 - 5 days old) were kept in microtitre wells containing 0,75 ml of liquid medium (with E. coli and without royal jelly extract) during 4 hours, then they were discarded and newborn larvae were transferred in next wells (with royal jelly extract in any concentration) every day (one worm in one well). This investigation was carried out in temperature +21C and in the darkness. The obtained results are presented in the following table. Concentration of royal Longevity jelly extract n mean +/- S.D. maximal 1:10*3 12 Lethal 1:10*4 11 18,2 +/- 1,8 28 1:10*5 12 19,2 +/- 2,2 32 1:10*6 12 19,3 +/- 1,7 28 1:10*7 12 15,8 +/- 2,2 28 1:10*8 11 20,6 +/- 3,1 32 1:10*9 8 12,3 +/- 3,5 34 1:10*10 12 17,5 +/- 2,3 31 Conclusion: If the extract from royal jelly was applied to C. elegans during the whole life span in above described conditions, the most effective concentration was 1:10*8. It seemed for me more reasonable to study the effect on longevity of any concentrations near 1:10*8. Acknowledgment: The author wishes to express his thanks to CGC for providing C. elegans (Bristol, N2) and E. coli OP50.
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[
Biochemistry,
2012]
Decapping scavenger (DcpS) enzymes catalyze the cleavage of a residual cap structure following 3' 5' mRNA decay. Some previous studies suggested that both m(7)GpppG and m(7)GDP were substrates for DcpS hydrolysis. Herein, we show that mononucleoside diphosphates, m(7)GDP (7-methylguanosine diphosphate) and m(3)(2,2,7)GDP (2,2,7-trimethylguanosine diphosphate), resulting from mRNA decapping by the Dcp1/2 complex in the 5' 3' mRNA decay, are not degraded by recombinant DcpS proteins (human, nematode, and yeast). Furthermore, whereas mononucleoside diphosphates (m(7)GDP and m(3)(2,2,7)GDP) are not hydrolyzed by DcpS, mononucleoside triphosphates (m(7)GTP and m(3)(2,2,7)GTP) are, demonstrating the importance of a triphosphate chain for DcpS hydrolytic activity. m(7)GTP and m(3)(2,2,7)GTP are cleaved at a slower rate than their corresponding dinucleotides (m(7)GpppG and m(3)(2,2,7)GpppG, respectively), indicating an involvement of the second nucleoside for efficient DcpS-mediated digestion. Although DcpS enzymes cannot hydrolyze m(7)GDP, they have a high binding affinity for m(7)GDP and m(7)GDP potently inhibits DcpS hydrolysis of m(7)GpppG, suggesting that m(7)GDP may function as an efficient DcpS inhibitor. Our data have important implications for the regulatory role of m(7)GDP in mRNA metabolic pathways due to its possible interactions with different cap-binding proteins, such as DcpS or eIF4E.
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[
Worm Breeder's Gazette,
1996]
It is well known that the royal jelly markedly prolongs the life span of honey bees. This substance is recommended by physicians for increasing of life quality. In this experiment royal jelly extract was used in the form of "Apilac" in dilutions 0,02% and 0,002%. The medium for control group was prepared by mixing S medium containing E. coli with S medium without E. coli (1:1). Three adult animals (3 - 5 days old) were kept in microtitre wells containing 0,75 ml of liquid medium (with E. coli and with or without royal jelly extract) during 6 hours, then they were discarded and newborn larvae were transferred in next wells every day (one worm in one well). Beginning from third day in the whole experiment was used the medium without this royal jelly extract. A number of progeny was calculated every day. This investigation was carried out in temperature +21C and in the darkness. The obtained results are presented in the following table. Control group Experimental Experimental group (0,02%) group (0,002%) n = 11 n = 11 n = 12 Mean +/- S.D. Mean +/- S.D. Mean +/- S.D Longevity (days): mean 19,4 +/- 1,2 18,0 +/- 1,7 21,8 +/- 1,2 maximal 25 27 26 minimal 10 9 14 Periods (days): prereproductive 2 2 2 reproductive 6,5 +/- 0,5 7,4 +/- 0,6 5,9 +/- 0,4 postreproductive 10,6 +/- 1,2 8,5 +/- 1,6 14,0 +/- 1,3 Fecundity: mean 158,8 +/- 6,6 93,9 +/- 9,9 128,9 +/- 3,4 maximal 197 179 153 minimal 115 60 111
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[
Worm Breeder's Gazette,
1994]
cej-1 Encodes a Novel Protein with Poly-Threonine Motif M. L. A. Khanl, M. Tabish, T. Fukushigel1 S. Tsukita2, M. Itoh , Sh. Tsukita , and S. S. Siddiqui. (1): Lab. of Molecular Biology, Dept of Ecological Engg. Toyohashi Univ. Technology, Toyohashi 441, and (2). National Institute for Physiological Sciences, Okazaki 444, Japan.
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[
Worm Breeder's Gazette,
1976]
We have studied maternal effects in 23 zyg ts mutants to estimate the times of expression of genes whose products are required in embryogenesis. We have used the following three tests, called arbitrarily A, B, and C. A test: Heterozygous (m/+) L4's are shifted to 25 C and allowed to self-fertilize. If 100% of their eggs yield larvae (25% of which express the mutant phenotype as adults), then the mutant is scored as maternal (M). If 25% of the F1 eggs fail to hatch, then the mutant is scored as non-maternal (N). An M result indicates that expression of the + allele in the parent allows m/m zygotes to hatch and grow to adulthood. A result of N indicates the opposite: that the + allele must be expressed in the zygote for hatching to occur. Out of 23 zyg mutants tested, 3 were scored N and 20 were scored M in the A test. Therefore, for most of the genes defined by these mutants, expression in the parent is sufficient for zygote survival, even if the gene is not expressed in the zygote. B test: Homozygous (m/m) hermaphrodites reared at 25 C are mated with N2 (+/+) males. If eggs fail to hatch at 25 C, but mated hermaphrodites shifted to 16 C produce cross progeny to give proof of mating, then the mutant is scored M. If cross progeny appear in the 25 C mating, then the mutant is scored N. An M result indicates that expression of the + allele in the zygote is not sufficient to allow m/+ progeny of an m/m hermaphrodite to survive. Conversely an N result indicates either that zygotic expression of the + allele is sufficient for survival, or that a sperm function or factor needed for early embryogenesis can be supplied paternally (see C test below). Out of the 23 zyg mutants tested, 11 were scored M and 12 were scored N. The combined results of A and B tests and their simplest interpretation are as follows. Ten mutants are M,M; the genes defined by these mutants must be expressed in the hermaphrodite parent for the zygote to survive. Ten mutants are M,N; these genes can be expressed either in the parent or in the zygote. Two mutants are N,N; these genes must be expressed in the zygote. One mutant is N,M; this gene must be expressed both in the maternal parent and in the zygote. C test: Homozygous (m/m) hermaphrodites reared at 25 C are mated with heterozygous (m/+) males. If rescue by a +/+ male in the B test depends on the + allele, then only half the cross progeny zygotes of a C test mating (m/+ male x m/m hermaphrodite) should survive. However, if rescue depends on a function or cytoplasmic component from the male sperm, then all the cross progeny zygotes in a C test should survive. Of the 10 M,N mutants, 6 have been C tested; one exhibited paternal rescue independent of the + allele. The A and B tests also were carried out on 16 mutants that arrest before the L3 molt (acc mutants). In the A test on 2 of these mutants, all m/m progeny of m/+ parents grew to adulthood at 25 C. Therefore, parental contributions are sufficient to overcome a progeny mutational block as late as the L2 stage. All 16 acc mutants scored N in the B test.
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[
Mech Ageing Dev,
2009]
Energy production via oxidative phosphorylation generates a mitochondrial membrane potential (DeltaPsi(m)) across the inner membrane. In this work, we show that a lower DeltaPsi(m) is associated with increased lifespan in Caenorhabditis elegans. The long-lived mutants
daf-2(
e1370),
age-1(
hx546),
clk-1(
qm30),
isp-1(
qm150) and
eat-2(
ad465) all have a lower DeltaPsi(m) than wild type animals. The lower DeltaPsi(m) of
daf-2(
e1370) is
daf-16 dependent, indicating that the insulin-like signaling pathway not only regulates lifespan but also mitochondrial energetics. RNA interference (RNAi) against 17 genes shown to extend lifespan also decrease DeltaPsi(m). Furthermore, lifespan can be significantly extended with the uncoupler carbonylcyanide-3-chlorophenylhydrazone (CCCP), which dissipates DeltaPsi(m). We conclude that longevity pathways converge on the mitochondria and lead to a decreased DeltaPsi(m). Our results are consistent with the 'uncoupling to survive' hypothesis, which states that dissipation of the DeltaPsi(m) will extend lifespan.
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[
Mol Genet Genomics,
2002]
Mutations in the Drosophila miniature-dusky ( m-dy) gene complex were first reported by Morgan and Bridges about 90 years ago. m-dy mutants have abnormally small wings, a phenotype attributed to a cell-autonomous reduction in the size of the epidermal cells comprising the differentiated wing. Using a molecular genetic approach, we have characterized the m-dy chromosomal interval and identified a pair of adjacent transcription units corresponding to m and dy. A dy mutant known as dy (And) has a single base substitution within the protein-coding region that is predicted to result in an amber stop codon and premature translational termination. We show that dy mRNA is expressed at two discrete periods during the life cycle - one during embryonic development and early larval instars, the second during adult development, coincident with wing differentiation. In agreement with the phenotypic similarity of m and dy mutants, sequence comparisons reveal a similarity between the predicted MINIATURE and DUSKY proteins, and indicate that the m and dy genes are members of a larger Drosophila gene family. Both m and dy, as well as other members of this superfamily, are predicted to encode transmembrane proteins with similarity to C. elegans cuticle proteins known as cuticulins. We postulate that m, dy and other members of this protein superfamily function as structural components of the Drosophila cuticulin layer. Such a role for m and dy products in wing differentiation is sufficient to explain the morphological phenotypes associated with m-dy mutants.
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[
Development & Evolution Meeting,
2008]
The C. elegans postembryonic mesodermal lineage, the M lineage, is a powerful model system to study mesodermal patterning and cell fate specification at single cell resolution. The M lineage arises from a single pluripotent cell, the M mesoblast, during embryogenesis. In hermaphrodites, the M cell undergoes a series of postembryonic cell divisions to produce 18 cells: 14 body wall muscles (BWMs), 2 coelomocytes (CCs), and 2 sex myoblasts (SMs). We and others have previously identified a handful of transcription factors important for the proper development of this lineage. In order to identify additional transcription factors that play a role in the M lineage, we have generated a feeding RNAi library that targets a majority of the predicted transcription factors encoded in the C. elegans genome and conducted an RNAi screen using cell type-specific GFP reporters in the M lineage. From this screen, we identified a novel set of 32 transcription factors that, upon RNAi knockdown, give reproducible phenotypes in the M lineage. Among these 32 transcription factors, four are important for patterning and fate specification of the early M lineage, while the rest appear to play a role in fate decisions in the SM lineage. We have primarily focused on
let-381, which encodes a forkhead transcription factor that is essential for C. elegans development.
let-381(RNAi) causes a dorsal to ventral fate transformation in the M lineage. We have found that a
let-381::gfp translational fusion is expressed in the dorsal M lineage. Previous studies from our lab have shown that SMA-9, the Sma/Mab TGF-beta and LIN-12/Notch signaling pathways are involved in dorsal/ventral patterning of the M lineage. We are currently investigating the relationship between
let-381 and these pathways.
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[
Cytoskeleton (Hoboken),
2024]
The M-line of striated muscle is a complex structure that anchors myosin-containing thick filaments and also participates in signaling and proteostasis. While the physical associations among many M-line components have been defined, the mechanism of thick filament attachment is not completely understood. In Caenorhabditis elegans, myosin A is essential for viability and forms the site of M-line attachment at the center of the filament, whereas myosin B forms the filament arms. Using a mutant myosin A that forms ectopic filaments, we examined interactions between myosin A and M-line proteins in intact muscle cells. Ectopic myosin A recruits the giant kinase UNC-89/obscurin, a presumed scaffolding protein, in an interaction that requires the zinc-finger protein UNC-98, but not UNC-82/NUAK, UNC-97/PINCH, or UNC-96. In myosin A mutants, UNC-89/obscurin patterning is highly defective in embryos and adults. A chimeric myosin containing 169 residues of the myosin A C-terminal rod, coincident with the UNC-98/ZnF binding site, is sufficient for colocalization of UNC-89/obscurin and UNC-98/ZnF in M-line structures whereas a myosin chimera lacking these residues colocalizes with UNC-89/obscurin in M-lines that lack UNC-98. Thus, at least two myosin A rod regions contribute independently to M-line organization. We hypothesize that these M-line-organizing functions correspond to the essential "filament initiation function" performed by this isoform.