Sima , a Drosophila homolog of HIF‐1α , in fat body tissue inhibits larval body growth by inducing Tribbles gene expression

The dorsal ectoderm of the Drosophila embryo is subdivided into different cell types by an activity gradient of two TGF(β) signaling molecules, Decapentaplegic (Dpp) and Screw (Scw). Patterning responses to this gradient depend on a secreted inhibitor, Short gastrulation (Sog) and a newly identified transcriptional repressor, Brinker (Brk), which are expressed in neurogenic regions that abut the dorsal ectoderm. Here we examine the expression of a number of Dpp target genes in transgenic embryos that contain ectopic stripes of Dpp, Sog and Brk expression. These studies suggest that the Dpp/Scw activity gradient directly specifies at least three distinct thresholds of gene expression in the dorsal ectoderm of gastrulating embryos. Brk was found to repress two target genes, tailup and pannier, that exhibit different limits of expression within the dorsal ectoderm. These results suggest that the Sog inhibitor and Brk repressor work in concert to establish sharp dorsolateral limits of gene expression. We also present evidence that the activation of Dpp/Scw target genes depends on the Drosophila homolog of the CBP histone acetyltransferase.

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Selective Increase in Human Heme Oxygenase-1 Gene Expression Attenuates Development of Hypertension and Increases Body Growth in Spontaneously Hypertensive Rats

Carbon Monoxide and Cardiovascular Functions ◽

10.1201/9781420041019.ch13 ◽

2001 ◽

pp. 233-245 ◽

Cited By ~ 2

Author(s):

Nader Abraham ◽

Shuo Quan ◽

Sylvia Shenouda ◽

Attallah Kappas

Keyword(s):

Gene Expression ◽

Heme Oxygenase ◽

Spontaneously Hypertensive Rats ◽

Body Growth ◽

Heme Oxygenase 1 ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Selective Increase

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Antiapoptotic activity of 30 kDa lipoproteins family from fat body tissue of silkworm,Bombyx mori

Insect Science ◽

10.1111/1744-7917.12119 ◽

2014 ◽

Vol 22 (5) ◽

pp. 629-638 ◽

Cited By ~ 5

Author(s):

Britto Cathrin Pakkianathan ◽

Nitin Kumar Singh ◽

Simone König ◽

Muthukalingan Krishnan

Keyword(s):

Bombyx Mori ◽

Fat Body ◽

Body Tissue ◽

Antiapoptotic Activity ◽

Silkworm Bombyx Mori

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Ovarian Development and Vitellogenin Gene Expression under Heat Stress in Silkworm,Bombyx mori

Psyche A Journal of Entomology ◽

10.1155/2016/4242317 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8

Author(s):

Satinath Paul ◽

Bela Keshan

Keyword(s):

Gene Expression ◽

Heat Stress ◽

Heat Shock ◽

Reproductive Performance ◽

Ovarian Development ◽

Fat Body ◽

Shock Treatment ◽

Heat Shock Treatment ◽

Vitellogenin Gene ◽

Vitellogenin Mrna

The present study observed the effect of heat stress on ovarian development, fecundity, and vitellogenin gene expression in silkworm,Bombyx mori. The result showed that the heat shock treatment to spinning larvae and pupae at 39°C (1 h and 2 h) did not cause any adverse effect on the reproductive performance ofB. mori.However, the heat shock treatment at 42°C or above caused a decrease in the fecundity. The heat shock treatment to day 2 pupae for 2 h at 45°C caused a drastic effect on the development of ovary as measured by gonadosomatic index. The study thus showed that a brief exposure ofBombyxlarvae and pupae to a temperature of 42°C or higher, much prevalent in tropical countries like India, greatly affects the ovarian development and reproductive performance of this commercially important insect. The study further showed a developmental- and tissue-specific expression of vitellogenin mRNA in fat body and ovary upon heat shock. When heat shock treatment was done at 39°C and 42°C to spinning larvae, ovary showed an upregulation in the expression of vitellogenin mRNA, whereas fat body failed to do so. However, at 45°C, both fat body and ovary showed a downregulation. The heat shock treatment to day 2 pupae showed an upregulation in the vitellogenin mRNA expression in both fat body and ovary, even at 45°C. The upregulation in the expression of vitellogenin upon heat shock indicates its role in thermal protection ofBombyxlarvae and pupae.

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Juvenile hormone signaling promotes ovulation and maintains egg shape by inducing expression of extracellular matrix genes

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2104461118 ◽

2021 ◽

Vol 118 (39) ◽

pp. e2104461118

Author(s):

Wei Luo ◽

Suning Liu ◽

Wenqiang Zhang ◽

Liu Yang ◽

Jianhua Huang ◽

...

Keyword(s):

Gene Expression ◽

Extracellular Matrix ◽

Muscle Contraction ◽

Juvenile Hormone ◽

Fat Body ◽

Collagen Iv ◽

Hormone Signaling ◽

Gonadotropic Hormone ◽

Egg Shape ◽

Insect Reproduction

It is well documented that the juvenile hormone (JH) can function as a gonadotropic hormone that stimulates vitellogenesis by activating the production and uptake of vitellogenin in insects. Here, we describe a phenotype associated with mutations in the Drosophila JH receptor genes, Met and Gce: the accumulation of mature eggs with reduced egg length in the ovary. JH signaling is mainly activated in ovarian muscle cells and induces laminin gene expression in these cells. Meanwhile, JH signaling induces collagen IV gene expression in the adult fat body, from which collagen IV is secreted and deposited onto the ovarian muscles. Laminin locally and collagen IV remotely contribute to the assembly of ovarian muscle extracellular matrix (ECM); moreover, the ECM components are indispensable for ovarian muscle contraction. Furthermore, ovarian muscle contraction externally generates a mechanical force to promote ovulation and maintain egg shape. This work reveals an important mechanism for JH-regulated insect reproduction.

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