The Role of 1‐Methylcyclopropene in the regulation of ethylene biosynthesis and ethylene receptor gene expression in
            Mangifera indica
            L. (Mango Fruit)

The Gonadotropins Subunits, GNRH and GNRH Receptor Gene Expression and Role of Carbon Monoxide in Seasonal Breeding AnimalsSeasonality in reproduction occurs mainly in wild species and it is the result of natural selection. Signals to start or finish the period of reproductive activity, both environmental and hormonal depend on the neuroendocrine pathway - synthesis and secretion of pituitary hormones, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), under the control of the hypothalamic gonadotropin-releasing hormone (GnRH) neurons. Variable frequency of GnRH pulses is not only the main factor governing primary and preovulatory release of gonadotropins, but it can also play a role in the specific transcriptional activity of gonadotropin subunit genes (LHβ, FSHβ and Cga). However, changes in release of GnRH pulse pattern do not explain the preferential stimulation of the synthesis and secretion of gonadotropins in the annual reproductive cycle. In this regulation also a GnRH independent mechanism participates. It seems that the main factor responsible for the occurrence of the seasonal modulation of reproduction in sheep and other mammals, is significant changes in response of GnRH systems to gonadal steroids. The effect of carbon monoxide on regulation of the hypothalamic-pituitary-gonadal axis has not been studied to date. There is substantial evidence to suggest that it may play a role in the transduction of information on day length. The presence of heme oxygenase-2 in hypothalamic areas important for regulation of pituitary secretory function and in the pituitary itself suggests that carbon monoxide, the product of this enzyme, may participate in the regulation of hormone secretion by the pineal gland.

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Relationship between Rh-RTH1 and ethylene receptor gene expression in response to ethylene in cut rose

Plant Cell Reports ◽

10.1007/s00299-010-0875-z ◽

2010 ◽

Vol 29 (8) ◽

pp. 895-904 ◽

Cited By ~ 6

Author(s):

Yixun Yu ◽

Jing Wang ◽

Huinan Wang ◽

Zhaoqi Zhang ◽

Juanxu Liu

Keyword(s):

Gene Expression ◽

Receptor Gene ◽

Ethylene Receptor ◽

Receptor Gene Expression ◽

Cut Rose

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Inhibition of Growth Hormone Receptor Gene Expression by Saturated Fatty Acids: Role of Krüppel-Like Zinc Finger Factor, ZBP-89

Molecular Endocrinology ◽

10.1210/me.2006-0128 ◽

2006 ◽

Vol 20 (11) ◽

pp. 2747-2760 ◽

Cited By ~ 18

Author(s):

Jamuna Thimmarayappa ◽

Jinhong Sun ◽

Laura E. Schultz ◽

Prapai Dejkhamron ◽

Chunxia Lu ◽

...

Keyword(s):

Gene Expression ◽

Diabetes Mellitus ◽

Palmitic Acid ◽

Receptor Gene ◽

Inhibitory Effect ◽

Cis Elements ◽

Gh Receptor ◽

Steady State Levels ◽

Receptor Gene Expression

Abstract The expression and function of the GH receptor is critical for the actions of pituitary GH in the intact animal. The role of systemic factors in the reduced expression of the GH receptor and consequent GH insensitivity in pathological states such as sepsis, malnutrition, and poorly controlled diabetes mellitus is unclear. In the current study, we demonstrate that saturated (palmitic and myristic; 50 μm) fatty acids (FA) inhibit activity of the promoter of the major (L2) transcript of the GH receptor gene; unsaturated (oleic and linoleic) FA (200 μm) do not alter activity of the promoter. Comparable effects with palmitic acid and the nonmetabolizable analog bromo-palmitic acid, and failure of triacsin C to abrogate palmitic acids effects on GH receptor expression indicate that this effect is due to direct action(s) of FA. Palmitic acid, but not the unsaturated FA linoleic acid, decreased steady-state levels of endogenous L2 mRNA and GHR protein in 3T3-L1 preadipocytes. The effect of FA was localized to two cis elements located approximately 600 bp apart on the L2 promoter. EMSA and chromatin immunoprecipitation assays established that both these cis elements bind the Krüppel-type zinc finger transcription factor, ZBP-89. Ectopic expression of ZBP-89 amplified the inhibitory effect of FA on L2 promoter activity and on steady-state levels of endogenous L2 mRNA in 3T3-L1 preadipocytes. Mutational analyses of the two ZBP-89 binding sites revealed that both the sites are essential for palmitic acid’s inhibitory effect on the L2 promoter and for the enhancing effect of ZBP-89 on palmitic acid-induced inhibition of the L2 promoter. Our results establish a molecular basis for FA-induced inhibition of GH receptor gene expression in the pathogenesis of acquired GH insensitivity in pathological states such as poorly controlled diabetes mellitus and small for gestational age.

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