Lint, a transmembrane serine protease, regulates growth and metabolism inDrosophila

AbstractInsulin signaling in Drosophila has a significant role in regulating growth, metabolism, fecundity, stress response, and longevity. The molecular mechanism by which insulin signaling regulates these vital processes is dependent on the nutrient status and oxygen availability of the organism. In a genetic screen to identify novel genes that regulate Drosophila insulin signaling, we discovered lumens interrupted (lint), a gene that has previously been shown to act in tracheal development. The knockdown of lint gene expression using a Dilp2Gal4 driver which expresses in the neuronal insulin producing cells (IPCs), led to defects in systemic insulin signaling, metabolic status and growth. However, our analysis of lint knockdown phenotypes revealed that downregulation of lint in the trachea and not IPCs was responsible for the growth phenotypes, as the Gal4 driver is also expressed in the tracheal system. We found various tracheal terminal branch defects, including reduction in the length as well as number of branches in the lint knockdown background. Our study reveals that substantial effects of lint downregulation arose because of tracheal defects, which induced tissue hypoxia, altered systemic insulin/TOR signaling, and resulted in effects on developmental growth regulation.

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Development of the Drosophila tracheal system occurs by a series of morphologically distinct but genetically coupled branching events

Development ◽

10.1242/dev.122.5.1395 ◽

1996 ◽

Vol 122 (5) ◽

pp. 1395-1407 ◽

Cited By ~ 52

Author(s):

C. Samakovlis ◽

N. Hacohen ◽

G. Manning ◽

D.C. Sutherland ◽

K. Guillemin ◽

...

Keyword(s):

Tube Formation ◽

The Body ◽

Terminal Branch ◽

Cellular Mechanisms ◽

Morphological Marker ◽

Tracheal System ◽

Fgf Receptor ◽

Restricted Domains ◽

Gene Regulatory ◽

Ets Domain

The tracheal (respiratory) system of Drosophila melanogaster is a branched network of epithelial tubes that ramifies throughout the body and transports oxygen to the tissues. It forms by a series of sequential branching events in each hemisegment from T2 to A8. Here we present a cellular and initial genetic analysis of the branching process. We show that although branching is sequential it is not iterative. The three levels of branching that we distinguish involve different cellular mechanisms of tube formation. Primary branches are multicellular tubes that arise by cell migration and intercalation; secondary branches are unicellular tubes formed by individual tracheal cells; terminal branches are subcellular tubes formed within long cytoplasmic extensions. Each level of branching is accompanied by expression of a different set of enhancer trap markers. These sets of markers are sequentially activated in progressively restricted domains and ultimately individual tracheal cells that are actively forming new branches. A clonal analysis demonstrates that branching fates are not assigned to tracheal cells until after cell division ceases and branching begins. We further show that the breathless FGF receptor, a tracheal gene required for primary branching, is also required to activate expression of markers involved in secondary branching and that the pointed ETS-domain transcription factor is required for secondary branching and also to activate expression of terminal branch markers. The combined morphological, marker expression and genetic data support a model in which successive branching events are mechanistically and genetically distinct but coupled through the action of a tracheal gene regulatory hierarchy.

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Exploring the Role of Insulin Signaling in Relative Growth: A Case Study on Wing-Body Scaling in Lepidoptera

Integrative and Comparative Biology ◽

10.1093/icb/icz080 ◽

2019 ◽

Vol 59 (5) ◽

pp. 1324-1337 ◽

Cited By ~ 6

Author(s):

Kenneth Z McKenna ◽

Della Tao ◽

H Frederik Nijhout

Keyword(s):

Body Size ◽

Insulin Signaling ◽

The Body ◽

Adult Size ◽

Tor Signaling ◽

Relative Growth ◽

Laboratory Populations ◽

Body Sizes ◽

Specific Variation ◽

Wing Growth

Abstract Adult forms emerge from the relative growth of the body and its parts. Each appendage and organ has a unique pattern of growth that influences the size and shape it attains. This produces adult size relationships referred to as static allometries, which have received a great amount of attention in evolutionary and developmental biology. However, many questions remain unanswered, for example: What sorts of developmental processes coordinate growth? And how do these processes change given variation in body size? It has become increasingly clear that nutrition is one of the strongest influences on size relationships. In insects, nutrition acts via insulin/TOR signaling to facilitate inter- and intra-specific variation in body size and appendage size. Yet, the mechanism by which insulin signaling influences the scaling of growth remains unclear. Here we will discuss the potential roles of insulin signaling in wing-body scaling in Lepidoptera. We analyzed the growth of wings in animals reared on different diet qualities that induce a range of body sizes not normally present in our laboratory populations. By growing wings in tissue culture, we survey how perturbation and stimulation of insulin/TOR signaling influences wing growth. To conclude, we will discuss the implications of our findings for the development and evolution of organismal form.

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Growth regulation and the insulin signaling pathway

Networks & Heterogeneous Media ◽

10.3934/nhm.2013.8.65 ◽

2013 ◽

Vol 8 (1) ◽

pp. 65-78 ◽

Cited By ~ 4

Author(s):

Peter W. Bates ◽

◽

Yu Liang ◽

Alexander W. Shingleton ◽

Keyword(s):

Signaling Pathway ◽

Insulin Signaling ◽

Growth Regulation ◽

Insulin Signaling Pathway

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Nutrient Availability and Growth: Regulation of Insulin Signaling by dFOXO/FOXO1

Cell Cycle ◽

10.4161/cc.5.5.2501 ◽

2006 ◽

Vol 5 (5) ◽

pp. 503-505 ◽

Cited By ~ 54

Author(s):

Oscar Puig ◽

Robert Tjian

Keyword(s):

Nutrient Availability ◽

Insulin Signaling ◽

Growth Regulation

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Furbellow (Brown Algae) Extract Increases Lifespan in Drosophila by Interfering with TOR-Signaling

Nutrients ◽

10.3390/nu12041172 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1172

Author(s):

Yang Li ◽

Renja Romey-Glüsing ◽

Navid Tahan Zadeh ◽

Jakob von Frieling ◽

Julia Hoffmann ◽

...

Keyword(s):

Insulin Signaling ◽

Brown Algae ◽

Molecular Mechanisms ◽

Fruit Fly ◽

Tor Signaling ◽

Signaling Systems ◽

Positive Effects ◽

Saccorhiza Polyschides ◽

Health Promoting ◽

Algal Products

Algal products are well known for their health promoting effects. Nonetheless, an in depth understanding of the underlying molecular mechanisms is still only fragmentary. Here, we show that aqueous furbelow extracts (brown algae, Saccorhiza polyschides) lengthen the life of both sexes of the fruit fly Drosophila melanogaster substantially, if used as nutritional additives to conventional food. This life prolonging effect became even more pronounced in the presence of stressors, such as high-fat dieting of living under drought conditions. Application of the extracts did not change food intake, excretion, or other major physiological parameters. Nevertheless, effects on the intestinal microbiota were observed, leading to an increased species richness, which is usually associated with healthy conditions. Lifespan extension was not observed in target of rapamycin (TOR)-deficient animals, implying that functional TOR signaling is necessary to unfold the positive effects of brown algae extract (BAE) on this important trait. The lack of life lengthening in animals with deregulated TOR signaling exclusively targeted to body fat showed that this major energy storage organ is instrumental for transmitting these effects. In addition, expression of Imaginal morphogenesis protein-Late 2 (Imp-L2), an effective inhibitor of insulin signaling implies that BAE exerts their positive effects through interaction with the tightly interwoven TOR- and insulin-signaling systems, although insulin levels were not directly affected by this intervention.

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Growth regulation and off-season flowering through night breaks in Chrysanthemum morifolium Ramat cv. Anmol

Bangladesh Journal of Botany ◽

10.3329/bjb.v48i2.47684 ◽

2019 ◽

Vol 48 (2) ◽

pp. 373-378

Author(s):

Tanya Thakur ◽

HS Grewal

Keyword(s):

Plant Growth ◽

Flowering Time ◽

Plant Height ◽

Growth Regulation ◽

Chrysanthemum Morifolium ◽

Morphological Development ◽

Chrysanthemum Morifolium Ramat ◽

Root Suckers ◽

Number Of Branches

The photoperiodic night interruption to schedule efficient flowering time in Chrysanthemum morifolium Ramat cv. Anmol according to demand of its flowers in the market was monitored. The influence of six night interruption treatments i.e. control, <5 second flash, 30, 60, 90 and 120 min were studied on the morphological development of Chrysanthemum morifolium Ramat cv. Anmol. The results revealed that the plant height, number of branches, leaves and root suckers per plant were positively affected with increased duration of night interruption. The flowering time was significantly delayed from mid December to end of February (two months) and number of flowers per plant increased as the duration of night interruption was increased from control to 120 min. Therefore, the night interruption durations studies were helpful to schedule the sustainable flowering time in Chrysanthemum cultivar Anmol by around two months with better plant growth.

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The transcription factors KNIRPS and KNIRPS RELATED control cell migration and branch morphogenesis during Drosophila tracheal development

Development ◽

10.1242/dev.125.24.4959 ◽

1998 ◽

Vol 125 (24) ◽

pp. 4959-4968 ◽

Cited By ~ 11

Author(s):

C.K. Chen ◽

R.P. Kuhnlein ◽

K.G. Eulenberg ◽

S. Vincent ◽

M. Affolter ◽

...

Keyword(s):

Transcription Factors ◽

Cell Migration ◽

Egf Receptor ◽

Regulatory Element ◽

Control Cell ◽

Terminal Branch ◽

Migration Behavior ◽

Related Activity ◽

Tracheal System ◽

Dorsal Branch

Cell migration during embryonic tracheal system development in Drosophila requires DPP and EGF signaling to generate the archetypal branching pattern. We show that two genes encoding the transcription factors KNIRPS and KNIRPS RELATED possess multiple and redundant functions during tracheal development. knirps/knirps related activity is necessary to mediate DPP signaling which is required for tracheal cell migration and formation of the dorsal and ventral branches. Ectopic knirps or knirps related expression in lateral tracheal cells respecifies their anteroposterior to a dorsoventral migration behavior, similar to that observed in the case of ectopic DPP expression. In dorsal tracheal cells knirps/knirps related activity represses the transcription factor SPALT; this repression is essential for secondary and terminal branch formation. However, in cells of the dorsal trunk, spalt expression is required for normal anteroposterior cell migration and morphogenesis. spalt expression is maintained by the EGF receptor pathway and, hence, some of the opposing activities of the EGF and DPP signaling pathways are mediated by spalt and knirps/knirps related. Furthermore, we provide evidence that the border between cells acquiring dorsal branch and dorsal trunk identity is established by the direct interaction of KNIRPS with a spalt cis-regulatory element.

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A Study on Distribution and Mode of Origin of Median Nerve and its Relation to the Flexor Retinaculum

Academia Anatomica International ◽

10.21276/aanat.2020.6.1.5 ◽

2020 ◽

Vol 6 (1) ◽

pp. 20-25

Author(s):

Atoofa Jaleel ◽

Ravinder M

Keyword(s):

Median Nerve ◽

Research Centre ◽

Terminal Branch ◽

Recurrent Nerve ◽

College Hospital ◽

Medical College ◽

Pronator Teres ◽

Flexor Retinaculum ◽

Precise Knowledge ◽

Number Of Branches

Introduction:The precise knowledge of level of origin of muscular branches of median nerve are essential in free muscular transfers to restore the mobility of fingers after trauma and to understand the various presentations of nerve entrapment. The anatomical knowledge and variations of recurrent nerve is important to prevent the complications during the release of transverse carpal ligament.Aim & Objectives: To study the points of origin of muscular branches with respect to IEL and number of branches to muscles of forearm and also learn the mode of origin of recurrent nerve and its relation to the flexor retinaculum.Subjects and Methods:Dissection 40 upper limbs procured from embalmed cadavers of Dr. VRK Women’s Medical College, Hospital and Research Centre, Hyderabad, for the study.Results:The mean of point of origin of NPT was 1.21 cm proximal and 1.20 cm distal to IEL whereas for NFCR, NPL, NFDS and AIN nerve it was 2.12 cm, cm, 4.54 cm and 3.29 cm distal to IEL respectively. The number of branches to muscles of forearm varied from 1 to 3. The recurrent nerve was arising from lateral and intermediate branches of median nerve in 39 (97.5%) and 1 specimens (6%) respectively. Its relationship with flexor retinaculum was extra ligamentous in 33 specimens (82.5%) and transligamentous in 7 specimens (17.5%). It innervated APB, FPB and OP in 19 specimens (47.5%), only APB, FPB in 16 specimens (45%) and only APB, OP in 3 specimens (7.5%).Conclusion:All the muscular branches of median nerve were arising predominantly distal to IEL except nerve to pronator teres. The number of branches varied from 1 to 3. In majority of the specimens, the recurrent nerve was arising from the lateral terminal branch of median nerve and its relation with flexor retinaculum was extraligamentous.

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Influence of zypmite on productivity and nutrient uptake of chickpea (Cicer arietinum L.) crop under rainfed condition Chhattisgarh plain region

Legume Research - An International Journal ◽

10.18805/lr-3586 ◽

2017 ◽

Cited By ~ 1

Author(s):

L. K. Shrivastava ◽

Awanish Kumar ◽

S. S. Senger ◽

V. N. Mishra ◽

Anusuiya Panda

Keyword(s):

Ammonium Phosphate ◽

Growth Yield ◽

Nutrient Status ◽

Chemical Fertilizers ◽

Available Nitrogen ◽

Rainfed Condition ◽

Nutrients Uptake ◽

Enhanced Yield ◽

Available Nutrient Status ◽

Number Of Branches

A field experiment was conducted to evaluate the effect of Zypmite fertilizer along with di-ammonium phosphate (DAP) in study. The application of Zypmite exhibited in growth, yield, nutrients uptake and availability of nutrient in soil. Zypmite response, the maximum number of branches (25.8 p-1), test weight (18.5 gm) and grain yield (17.10 q ha-1) was observed with 50 kg P2O5 through DAP + 40 kg S through Zypmite (T6). The nitrogen (69.52 kg ha-1) and phosphorous (7.89 kg ha-1) uptake was also found maximum under T6 and minimum in control (T1). The potassium (39.27 kg ha-1) and sulphur (7.85 kg ha-1) uptake was observed maximum under 50 kg P2O5 through DAP + 20 kg S through Zypmite (T5). After harvesting of crop, available nutrient status was observed higher available nitrogen (243.0 kg ha-1) under T6 and available phosphorous was significantly higher in T2 and T9 (18.0 kg ha-1) as compared to control. Availability of potassium in all treatments was significantly not influenced during both years. The sulphur availability in soil was significantly influenced among treatment and found maximum (23.0 kg ha-1) under 40 kg sulphur through Zypmite (T7). It was observed that Zypmite and chemical fertilizers, enhanced yield and higher uptake of nutrient as well as improved soil fertility.

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