Related Experiment Video
Updated: Aug 20, 2025
05:36
A Tissue Culture Model of Estrogen-producing Primary Bovine Granulosa Cells
Published on: September 6, 2018
9.3K
AKAP13 Enhances CREB1 Activation by FSH in Granulosa Cells.
Kamaria C Cayton Vaught1, Dana Hazimeh2, Ashlie Sewdass Carter3
1Division of Reproductive Sciences & Women's Health Research, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA. Kcayton1@jhmi.edu.
Reproductive Sciences (Thousand Oaks, Calif.)
|November 18, 2022
Summary
A-kinase anchoring protein 13 (AKAP13) acts as a scaffold protein in granulosa cells, mediating follicle-stimulating hormone (FSH) signaling. It enhances FSH-induced CREB1 phosphorylation and aromatase activity, crucial for follicle maturation.
Area of Science:
- Reproductive Biology
- Cell Signaling
- Molecular Endocrinology
Background:
- Granulosa cells (GCs) require proper response to follicle-stimulating hormone (FSH) for ovarian follicle maturation.
- FSH signaling involves protein kinase A (PKA) activation and cyclic AMP response element binding protein-1 (CREB1) phosphorylation.
Purpose of the Study:
- To investigate the role of A-kinase anchoring protein 13 (AKAP13) in GC response to FSH.
- To elucidate the mechanism by which AKAP13 influences FSH-mediated signaling pathways.
Main Methods:
- Overexpression and siRNA knockdown of AKAP13 in human and murine GCs.
- Aromatase reporter assays and Western blotting for CREB1 phosphorylation.
- Co-immunoprecipitation to assess protein interactions.
- Inhibition and activation of the Rho guanine nucleotide exchange factor (RhoGEF) domain of AKAP13.
Main Results:
- AKAP13 overexpression enhanced FSH- and forskolin-induced aromatase reporter activity.
- AKAP13 physically interacted with CREB1 and increased its phosphorylation in an FSH-dependent manner.
- AKAP13 knockdown reduced FSH-induced aromatase and luteinizing hormone receptor transcripts.
- RhoGEF activity of AKAP13 modulated aromatase reporter activity.
Conclusions:
- AKAP13 functions as a scaffolding protein in FSH signal transduction within GCs.
- AKAP13 facilitates FSH-induced CREB1 phosphorylation, impacting key gene expression for follicle maturation.
- AKAP13's RhoGEF domain plays a role in regulating FSH-mediated cellular responses.
Related Concept Videos
01:20Folliculogenesis
962
Folliculogenesis is the development of ovarian follicles, the specialized structures within the ovarian cortex where oogenesis, or egg development, occurs. This process is essential for female reproductive health and begins during fetal development when primordial follicles are formed. Each primordial follicle comprises a primary oocyte in the center, surrounded by a single layer of squamous pre-granulosa cells. These follicles remain dormant in late prophase I of meiosis until triggered by...
962
01:29Somatic to iPS Cell Reprogramming
2.3K
Reprogramming alters the gene expression in somatic cells, transforming them into induced pluripotent stem (iPS) cells over several generations. Scientists can reprogram cells by introducing genes for four transcription factors—Oct4, Sox2, Klf4, and c-Myc (OSKM) by viral or non-viral methods. These factors are also known as Yamanaka factors after Shinya Yamanaka, who first generated iPS cells using mouse skin cells. Yamanaka was awarded the Nobel Prize in Physiology or Medicine in 2012...
2.3K
01:27Feedback Regulation of Calcium Concentration
3.4K
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
3.4K
01:22Target Cell Response to Hormones
3.2K
Hormones intricately bind to receptors on the surface or within target cells, initiating a cascade of cellular responses.
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
3.2K
01:41Spermatogenesis
102.9K
Spermatogenesis is the process by which haploid sperm cells are produced in the male testes. It starts with stem cells located close to the outer rim of seminiferous tubules. These spermatogonial stem cells divide asymmetrically to give rise to additional stem cells (meaning that these structures “self-renew”), as well as sperm progenitors, called spermatocytes. Importantly, this method of asymmetric mitotic division maintains a population of spermatogonial stem cells in the male...
102.9K
01:25cAMP-dependent Protein Kinase Pathways
6.5K
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...
6.5K