In situ localization of the per clock protein during development of Drosophila melanogaster.

The per locus influences biological rhythms in Drosophila melanogaster. In this study, per transcripts and proteins were localized in situ in pupae and adults. Earlier genetic studies have demonstrated that per expression is required in the brain for circadian locomotor activity rhythms and in the thorax for ultradian rhythmicity of the Drosophila courtship song. per RNA and proteins were detected in a restricted group of cells in the eyes and optic lobes of the adult brain and in many cell bodies in the adult and pupal thoracic ganglia. per products were also found in the pupal ring gland complex, a tissue involved in rhythmic aspects of Drosophila development. Abundant expression was seen in gonadal tissue. No biological clock phenotypes have been reported for this tissue in any of the per mutants, per protein mapped to different subcellular locations in different tissues. The protein accumulated in or around nuclei in some cells and appeared to be cytoplasmic in others.

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Stem cell application in neurorehabilitation

Oxford Textbook of Neurorehabilitation ◽

10.1093/med/9780198824954.003.0014 ◽

2020 ◽

pp. 169-184

Author(s):

Sebastian Jessberger ◽

Armin Curt ◽

Roger A. Barker

Keyword(s):

Spinal Cord ◽

Stem Cells ◽

Stem Cell ◽

Adult Brain ◽

Proper Function ◽

Great Promise ◽

Neuropsychiatric Diseases ◽

Brain And Spinal Cord ◽

The Brain

A number of diseases of the brain and spinal cord are associated with substantial neural cell death and/or disruption of correct and functional neural networks. In the past, a variety of therapeutic strategies to rescue these systems have been proposed along with agents to induce functional plasticity within the remaining central nervous system (CNS) structures. In the case of injury or neurodegenerative disease these approaches have only met with limited success, indicating the need for novel approaches to treat diseases of the adult CNS. Recently, the idea of recruiting endogenous or transplanting stem cells to replace lost structures within the adult brain or spinal cord has gained significant attention, along with in situ reprogramming, and opened up novel therapeutic avenues in the context of regenerative medicine. Here we review recent advances in our understanding of how endogenous stem cells may be a part of pathological processes in certain neuropsychiatric diseases and summarize recent clinical and preclinical data suggesting that stem cell-based therapies hold great promise as a future treatment option in a number of diseases disrupting the proper function of the adult CNS.

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Expression of the Cystathionine β Synthase (CBS) Gene During Mouse Development and Immunolocalization in Adult Brain

Journal of Histochemistry & Cytochemistry ◽

10.1177/002215540305100311 ◽

2003 ◽

Vol 51 (3) ◽

pp. 363-371 ◽

Cited By ~ 94

Author(s):

Karine Robert ◽

François Vialard ◽

Eric Thiery ◽

Kiyoko Toyama ◽

Pierre-Marie Sinet ◽

...

Keyword(s):

Plasma Concentrations ◽

Northern Blotting ◽

Adult Brain ◽

Spatial And Temporal Patterns ◽

Mouse Development ◽

Cellular Expression ◽

Brain Expression ◽

Neuronal Processes ◽

The Brain

Hyperhomocysteinemia, caused by a lack of cystathionine β synthase (CBS), leads to elevated plasma concentrations of homocysteine. This is a common risk factor for atherosclerosis, stroke, and possibly neurodegenerative diseases. However, the mechanisms that link hyperhomocysteinemia due to CBS deficiency to these diseases are still unknown. Early biochemical studies describe developmental and adult patterns of transsulfuration and CBS expression in a variety of species. However, there is incomplete knowledge about the regional and cellular expression pattern of CBS, notably in the brain. To complete the previous data, we used in situ hybridization and Northern blotting to characterize the spatial and temporal patterns of Cbs gene expression during mouse development. In the early stages of development, the Cbs gene was expressed only in the liver and in the skeletal, cardiac, and nervous systems. The expression declined in the nervous system in the late embryonic stages, whereas it increased in the brain after birth, peaking during cerebellar development. In the adult brain, expression was strongest in the Purkinje cell layer and in the hippocampus. Immunohistochemical analyses showed that the CBS protein was localized in most areas of the brain but predominantly in the cell bodies and neuronal processes of Purkinje cells and Ammon's horn neurons.

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The Mouse Murr1 Gene Is Imprinted in the Adult Brain, Presumably Due to Transcriptional Interference by the Antisense-Oriented U2af1-rs1 Gene

Molecular and Cellular Biology ◽

10.1128/mcb.24.1.270-279.2004 ◽

2004 ◽

Vol 24 (1) ◽

pp. 270-279 ◽

Cited By ~ 59

Author(s):

Youdong Wang ◽

Keiichiro Joh ◽

Sadahiko Masuko ◽

Hitomi Yatsuki ◽

Hidenobu Soejima ◽

...

Keyword(s):

Developmental Change ◽

Adult Brain ◽

Paternal Allele ◽

Transcriptional Interference ◽

Specific Expression ◽

Biallelic Expression ◽

Allele Specific ◽

The Brain ◽

Predominant Expression

ABSTRACT The mouse Murr1 gene contains an imprinted gene, U2af1-rs1, in its first intron. U2af1-rs1 shows paternal allele-specific expression and is transcribed in the direction opposite to that of the Murr1 gene. In contrast to a previous report of biallelic expression of Murr1 in neonatal mice, we have found that the maternal allele is expressed predominantly in the adult brain and also preferentially in other adult tissues. This maternal-predominant expression is not observed in embryonic and neonatal brains. In situ hybridization experiments that used the adult brain indicated that Murr1 gene was maternally expressed in neuronal cells in all regions of the brain. We analyzed the developmental change in the expression levels of both Murr1 and U2af1-rs1 in the brain and liver, and we propose that the maternal-predominant expression of Murr1 results from transcriptional interference of the gene by U2af1-rs1 through the Murr1 promoter region.

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Neurotransmitter Classification from Electron Microscopy Images at Synaptic Sites in Drosophila

10.1101/2020.06.12.148775 ◽

2020 ◽

Cited By ~ 2

Author(s):

Nils Eckstein ◽

Alexander S. Bates ◽

Michelle Du ◽

Volker Hartenstein ◽

Gregory S.X.E. Jefferis ◽

...

Keyword(s):

Electron Microscopy ◽

Drosophila Melanogaster ◽

Statistical Significance ◽

High Resolution Electron Microscopy ◽

Adult Brain ◽

Average Accuracy ◽

Resolution Electron ◽

High Statistical Significance ◽

Fast Acting ◽

The Brain

AbstractHigh-resolution electron microscopy (EM) of nervous systems enables the reconstruction of neural circuits at the level of individual synaptic connections. However, for invertebrates, such as Drosophila melanogaster, it has so far been unclear whether the phenotype of neurons or synapses alone is sufficient to predict specific functional properties such as neurotransmitter identity. Here, we show that in Drosophila melanogaster artificial convolutional neural networks can confidently predict the type of neurotransmitter released at a synaptic site from EM images alone. The network successfully discriminates between six types of neurotransmitters (GABA, glutamate, acetylcholine, serotonin, dopamine, and octopamine) with an average accuracy of 87% for individual synapses and 94% for entire neurons, assuming each neuron expresses only one neurotransmitter. This result is surprising as there are often no obvious cues in the EM images that human observers can use to predict neurotransmitter identity. We apply the proposed method to quantify whether, similar to the ventral nervous system (VNS), all hemilineages in the Drosophila melanogaster brain express only one fast acting transmitter within their neurons. To test this principle, we predict the neurotransmitter identity of all identified synapses in 89 hemilineages in the Drosophila melanogaster adult brain. While the majority of our predictions show homogeneity of fast-acting neurotransmitter identity within a single hemilineage, we identify a set of hemilineages that express two fast-acting neurotransmitters with high statistical significance. As a result, our predictions are inconsistent with the hypothesis that all neurons within a hemilineage express the same fast-acting neurotransmitter in the brain of Drosophila melanogaster.

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LIPID PEROXIDATION IN DEVELOPING RAT BRAIN

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o61-129 ◽

1961 ◽

Vol 39 (8) ◽

pp. 1231-1238 ◽

Cited By ~ 72

Author(s):

E. T. Pritchard ◽

H. Singh

Keyword(s):

Lipid Peroxidation ◽

Fatty Acid ◽

Rat Brain ◽

Polyunsaturated Fatty Acid ◽

Thiobarbituric Acid ◽

Adult Brain ◽

Fatty Acid Peroxidation ◽

Developing Rat ◽

The Brain

The experimental results indicate that the production of thiobarbituric acid (TBA) positive material, apparently derived for the most part from polyunsaturated fatty acid peroxidation, decreases with maturation of rat brain. It appears that during maturation some factor or process is gradually introduced into, or generated within, the brain which retards the tendency of unsaturates to undergo oxidation in situ. This process is possibly related to the maintenance of stability in adult brain.

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Tissue localization of Drosophila melanogaster ras transcripts during development.

Molecular and Cellular Biology ◽

10.1128/mcb.6.6.2241 ◽

1986 ◽

Vol 6 (6) ◽

pp. 2241-2248 ◽

Cited By ~ 32

Author(s):

D Segal ◽

B Z Shilo

Keyword(s):

Drosophila Melanogaster ◽

Tissue Distribution ◽

Adult Stage ◽

Multiple Roles ◽

Similar Distribution ◽

Ras Proteins ◽

Dividing Cells ◽

Imaginal Disks ◽

The Brain

Three ras homologs have been identified in Drosophila melanogaster. Here we describe the tissue distribution of their transcripts as analyzed by in situ hybridization. The RNAs of the three genes show a similar distribution at every developmental stage examined. In embryos, the transcripts are uniformly distributed. In larvae, ras transcripts are restricted to dividing cells (e.g., imaginal disks, gonads, and brain). At the adult stage, several tissues contain ras transcripts. The strongest hybridization signals are localized to the adult ovaries and to the cortex of the brain and ganglia, which at this stage are comprised of differentiated, nondividing cells. The tissue distribution of ras transcripts in D. melanogaster suggests that the ras proteins have multiple roles during development which may be related to both the proliferative and differentiated states of the tissues.

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Tissue localization of Drosophila melanogaster ras transcripts during development

Molecular and Cellular Biology ◽

10.1128/mcb.6.6.2241-2248.1986 ◽

1986 ◽

Vol 6 (6) ◽

pp. 2241-2248

Author(s):

D Segal ◽

B Z Shilo

Keyword(s):

Drosophila Melanogaster ◽

Tissue Distribution ◽

Adult Stage ◽

Multiple Roles ◽

Similar Distribution ◽

Ras Proteins ◽

Dividing Cells ◽

Imaginal Disks ◽

The Brain

Three ras homologs have been identified in Drosophila melanogaster. Here we describe the tissue distribution of their transcripts as analyzed by in situ hybridization. The RNAs of the three genes show a similar distribution at every developmental stage examined. In embryos, the transcripts are uniformly distributed. In larvae, ras transcripts are restricted to dividing cells (e.g., imaginal disks, gonads, and brain). At the adult stage, several tissues contain ras transcripts. The strongest hybridization signals are localized to the adult ovaries and to the cortex of the brain and ganglia, which at this stage are comprised of differentiated, nondividing cells. The tissue distribution of ras transcripts in D. melanogaster suggests that the ras proteins have multiple roles during development which may be related to both the proliferative and differentiated states of the tissues.

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Biological rhythms in Arctic vertebrates

Rangifer ◽

10.7557/2.20.2-3.1506 ◽

2000 ◽

Vol 20 (2-3) ◽

pp. 99 ◽

Cited By ~ 1

Author(s):

B. E.H. Van Oort ◽

N. J.C. Tyler ◽

E. Reierth ◽

K.-A. Stokkan

Keyword(s):

Rangifer Tarandus ◽

Biological Clock ◽

Biological Rhythms ◽

Polar Regions ◽

Physiological Control ◽

Endogenous Rhythms ◽

Arctic Species ◽

Cyclical Fluctuations ◽

Timing Mechanisms ◽

The Brain

Many biological processes show regular cyclical fluctuations that persist throughout an organism's life; these range from the transcription of DNA to patterns of behaviour. Persistent, cyclical phenomena of this kind are a fundamental feature of all organisms. They are governed primarily by endogenous rhythms generated by a 'biological clock' situated in the brain. Normally, however, the expression of the clock is modulated to a greater or lesser extent by environmental cues. This paper reviews the physiological control of the temporal organisation of cycles in vertebrates and, in particular, explores their regulation in arctic species like reindeer (Rangifer tarandus L.). We emphasise how exposure to the photoperiodic conditions that characterise polar regions places special demands on timing mechanisms and how arctic species, therefore, are of particular interest for the study of biological rhythms. Thus far, behavioural and physiological studies of these species show that arctic reindeer (and ptarmigan) appear to be truly opportunistic in summer and wintet, seemingly without any active biological clock and that they are, instead, driven directly by photoperiod. This situation, if confirmed, would be unique among vertebrates.

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Extra Visual Function of the Human Eye.

10.46940/cjoec.02.1003 ◽

2020 ◽

pp. 1-6

Keyword(s):

Biological Clock ◽

Biological Rhythms ◽

Visual Image ◽

Photochemical Activity ◽

Electrical Signal ◽

The Body ◽

Scotopic Vision ◽

Rods And Cones ◽

Organ Systems ◽

The Brain

Abstract The eye is part of the sensory nervous system. However, there are a number of organ systems that also work with the eye. The retina is the only tissue in mammals that regulates photoreception due to the presence of photoreceptors, the rods and cones and performs both visual and non-visual functions Light plays a fundamental role in the behavior of almost all organisms. In addition to visual processes, light also induces important physiological responses. People with mild vascular disease that causes damage to the retina in the eye are more likely to have problems with thinking and memory skills. Everyone has a natural body clock that they are born with and all organs in the body operate according to biological rhythms. Our experiments with ophthalmic mutant rats also showed that the loss of vision also hampered their physiological activities and their rhythmicity was also disturbed. The menstrual cycle disturbances and age of menarche are regulated by many factors; nevertheless, blindness is one of the most impotent factors in regulating biological clock dependent functions. The human eyes are the only organs in the body capable of “seeing”- wavelengths of light and turning it into visual images. We can't “see” or get a visual image to the brain without eyes. The eye-like ability of skin to sense light by using a receptor (Cryptochrome) but failed to form image. Photoreceptors contain chemicals that change when they are hit by light. This causes an electrical signal, which is then sent to the brain along the optic nerve. Different types of photoreceptor allow us to see an enormous range of light and colours. There are two types of photoreceptors in the human retina, rods and cones. Rods are responsible for vision at low light levels (scotopic vision). They do not mediate colour vision and have a low spatial acuity. The blind: People who have lost their sight have different experiences. Some describe seeing complete darkness, like being in a cave. Some people see sparks or experience vivid visual hallucinations that may take the form of recognizable shapes, random shapes and colours, or flashes of light. An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image. Afterimages occur because photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus.

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