Follicle-stimulating hormone (FSH) comprises an alpha subunit and a beta subunit, whereas the FSH receptor consists of two halves with distinct functions: the N-terminal extracellular exodomain and C-terminal membrane-associated endodomain. FSH initially binds to exodomain, and the resulting FSH/exodomain complex modulates the endodomain and generates signal. However, it has been difficult to determine which subunit of FSH contacts the exodomain or endodomain and in what orientation FSH interacts with them. To address these crucial issues, the receptor was Ala-scanned and the hormone subunits were probed with photoaffinity labeling with receptor peptides corresponding to the N-terminal region of the exodomain and exoloop 3 of the endodomain. Our results show that both regions of the receptors are important for hormone binding and signal generation. In addition, the FSH beta subunit is specifically labeled with the N-terminal peptide, whereas the alpha subunit is labeled with the exoloop 3 peptide. These contrasting results show that the FSH beta subunit is close to the N-terminal region and that the alpha subunit is projected toward exoloop 3 in the endodomain. The results raise the fundamental question whether the alpha subunit, common among the glycoprotein hormones, plays a major role in generating the hormone signal common to all glycoprotein hormones.

Download full-text PDF

Source
http://dx.doi.org/10.1074/jbc.M307751200DOI Listing

Publication Analysis

Top Keywords

alpha subunit
20
beta subunit
16
subunit
10
fsh
9
follicle-stimulating hormone
8
hormone fsh
8
fsh receptor
8
subunit fsh
8
n-terminal region
8
exoloop endodomain
8

Similar Publications

Aim: This study focuses on the design and investigation a transethosomal formulation for enhanced topical delivery and improved analgesic activity of caryophyllene oxide. In addition, this work explores new potential mechanisms of analgesic activity of the active compound including alpha-amino-3-hydroxy-5-methyl-4-isooxazole-propionic acid (AMPA) and Cyclooxygenase 2 (COX-2).

Methods: The transethosomal system containing various caryophyllene concentrations was prepared.

View Article and Find Full Text PDF

In animal cells, Gα subunit of the heterotrimeric G proteins can bind to both the N-terminal and C-terminal domains of G-protein-activated inwardly rectifying K channels (GIRKs) to inhibit their activities. In Arabidopsis guard cells, the Gα subunit GPA1 mediates multiple stimuli-regulated stomatal movements via inhibiting guard cell inward-rectifying K (K) current, but it remains unclear whether GPA1 directly interacts with and inhibits the activities of K channels. Here, we found that GPA1 interacted with the transmembrane domain rather than the intracellular domain of the Shaker family K channel KAT1.

View Article and Find Full Text PDF

Mitochondrial dysfunction and α-synuclein (αSyn) aggregation are key contributors to Parkinson's Disease (PD). While genetic and environmental risk factors, including mutations in mitochondrial-associated genes, are implicated in PD, the precise mechanisms linking mitochondrial defects to αSyn pathology remain incompletely understood, hindering the development of effective therapeutic interventions. Here, we identify the loss of branched chain ketoacid dehydrogenase kinase (BCKDK) as a mitochondrial risk factor that exacerbates αSyn pathology by disrupting Complex I function.

View Article and Find Full Text PDF

Changing Paradigms in Asthma Management.

Am J Med Sci

December 2024

Division of Clinical Immunology, The University of Mississippi Medical Center, Jackson, MS. Electronic address:

Asthma is a complex clinical syndrome characterized by airway inflammation that can cause variable, usually reversible airway obstruction and bronchial hyperreactivity. This illness has a spectrum from intermittent to persistent that has mild, medium or severe intensity. As our understanding of the underling inflammatory pathway grows, so too does our catalogue of advanced treatments (such as monoclonal antibodies), opening the path for treatment individually curated for patients.

View Article and Find Full Text PDF

Vaccination with formulations targeting Eimeria maxima and Clostridium perfringens conferred comprehensive protection using a dual-infection challenge model of necrotic enteritis.

Poult Sci

December 2024

MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China; Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA. Electronic address:

With increasing regulations restricting antibiotic use in animal feed, the need for alternative strategies to prevent and manage necrotic enteritis (NE) has become imperative. As a result, developing effective vaccines has emerged as a top priority for broiler chicken health management. Coccidial infections are a well-established predisposing factor for NE, underscoring the importance of controlling coccidiosis to help mitigate NE outbreaks.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!