Video Experimental Relacionado
Updated: Nov 24, 2025
11:14
Modeling Paracrine Noncanonical Wnt Signaling In Vitro
Published on: December 10, 2021
1.8K
Bases estructurales del transporte y la secreción de WLS/Wnt mediado por Evi
Rie Nygaard1, Jia Yu2, Jonathan Kim1
1Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY 10032, USA.
Cell
|December 28, 2020
Resumen
Los investigadores revelan la estructura de la proteína Wnt unida a su transportador Wntless (WLS), descubriendo detalles moleculares de la secreción de Wnt cruciales para el desarrollo animal y la renovación de las células madre.
Área de la Ciencia:
- Biología molecular
- Biología del desarrollo
- Biología estructural
Sus antecedentes:
- Las proteínas Wnt son moléculas de señalización esenciales que regulan el destino celular, la morfogénesis y la renovación de las células madre.
- La secreción de Wnt requiere la O-palmitulación y el transporte por Wntless (WLS/Evi).
Objetivo del estudio:
- Determinar la estructura de alta resolución del WNT8A palmitoilado en complejo con el WLS.
- Para aclarar el mecanismo molecular de la carga de Wnt en su transportador WLS.
Principales métodos:
- Microscopía electrónica criogénica (cryo-EM) con una resolución de 3,2 Å.
- Experimentos bioquímicos para investigar las interacciones Wnt-WLS y su relevancia fisiológica.
Principales resultados:
- La estructura revela que WLS tiene un dominio de membrana homólogo a los receptores acoplados a proteínas G (GPCR).
- Una horquilla Wnt se inserta en una cavidad hidrofóbica dentro del dominio similar a GPCR de WLS.
- La modificación palmitoleate de Wnt interactúa con la región incrustada en la membrana WLS.
Conclusiones:
- La estructura del complejo Wnt-WLS proporciona información molecular sobre la secreción de Wnt.
- Un posible cambio conformacional en Wnt puede facilitar la transferencia a las células receptoras.
- Este mecanismo es fundamental para el desarrollo del plan corporal animal y la biología de las células madre.
Videos de Conceptos Relacionados
01:41Non-Canonical Wnt Signaling Pathways
8.0K
Wnt is a zygotic effect gene that is expressed during very early embryonic development. It regulates various processes in animals starting from early development through the adult stage, such as organogenesis in the embryo and maintenance of neuronal and blood stem cells. Wnt proteins can induce a wide variety of intracellular pathways depending upon the specific abilities of different Wnt ligands to form a complex with shared and cognate receptors in the presence of different co-receptors. The...
8.0K
01:22Role of Ephrin-Eph Signalling in Intestinal Stem Cell Renewal
2.4K
Erythropoietin-producing hepatocellular carcinoma receptor (Eph) and its ligand, Eph receptor-interacting protein (Ephrin) were first discovered in the human carcinoma cell line, hence the name. Ephrin-Eph interaction guides cells to reach their appropriate location in adult tissues. They also play an essential role in the immune system by helping in immune cell migration, adhesion, and activation. Based on their structure and function, Eph is divided into two classes — EphA and EphB.
2.4K
02:54Canonical Wnt Signaling Pathway
9.8K
The gene encoding the main signaling molecules of the Wnt signaling pathways (the Wnt proteins) was discovered almost four decades ago by Nüsslein-Volhard and Wieschaus. They identified and originally named the gene "wingless" (wg) after a phenotype discovered during their landmark genetic screen in Drosophila for body pattern defects. At around the same time, another researcher named Harold Varmus found that a murine tumor virus activates the mammalian wg homolog, Int-1, which...
9.8K
01:31Mechanism of Lamellipodia Formation
3.3K
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
3.3K
01:33Overview of Secretory Vesicles
9.1K
Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
9.1K
00:55Laminins are the Adhesive Proteins of Basal Lamina
2.7K
Laminins are heterotrimeric proteins with high molecular mass found in the extracellular matrix. Each laminin molecule is composed of three chains, viz. alpha, beta, and gamma, coded by five, four, and three paralogous genes, respectively. Laminins are categories based on the compositions of the three chains.
In humans, the five forms of alpha chains are LAMA 1, LAMA 2, LAMA 3, LAMA 4, and LAMA 5. The four forms of beta chains are LAMB 1, LAMB 2, LAMB 3, and LAMB 4. The three forms of gamma...
In humans, the five forms of alpha chains are LAMA 1, LAMA 2, LAMA 3, LAMA 4, and LAMA 5. The four forms of beta chains are LAMB 1, LAMB 2, LAMB 3, and LAMB 4. The three forms of gamma...
2.7K