Video Experimental Relacionado

Updated: Sep 18, 2025

Analysis of Protein Import into Chloroplasts Isolated from Stressed Plants

Analysis of Protein Import into Chloroplasts Isolated from Stressed Plants

Published on: November 1, 2016

Un orgánulo huésped integra los cloroplastos robados para la fotosíntesis animal

Corey A H Allard¹, Angus B Thies², Rishav Mitra³

¹Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.

|June 26, 2025

Resumen

Las babosas marinas albergan cloroplastos robados en nuevos "cleptosomas", que permiten la fotosíntesis animal. Estos orgánulos derivados del huésped apoyan a los cloroplastos y proporcionan nutrientes durante la inanición, revelando una evolución convergente en los animales fotosintéticos.

Área de la Ciencia:

Endosimbiosis y evolución de los orgánulos
Interacciones entre animales y plantas
Biología molecular y celular

Sus antecedentes:

Las células eucariotas evolucionaron a través de la endosimbiosis, integrando a los procariotas en las mitocondrias y los cloroplastos.
Las babosas marinas de Sacoglossan pueden retener cloroplastos funcionales durante períodos prolongados, lo que permite la "fotosíntesis animal".
El mecanismo detrás de esta fotosíntesis sostenida y retención de orgánulos era previamente desconocido.

Objetivo del estudio:

Elucidar el mecanismo por el cual las babosas marinas mantienen los cloroplastos fotosintéticamente activos.
Para identificar las estructuras derivadas del huésped que albergan estos orgánulos extraños.
Investigar las implicaciones evolutivas de la adquisición de simbiontes intracelulares en animales.

Principales métodos:

Microscopía e imágenes celulares para identificar y caracterizar nuevos orgánulos.
Ensayos bioquímicos para analizar el entorno luminoso de estos orgánulos.
Análisis comparativo entre diferentes especies de animales fotosintéticos.

Principales resultados:

Los cloroplastos extraños están encerrados dentro de orgánulos derivados del huésped llamados "cleptosomas".
Los cleptosomas utilizan canales iónicos sensibles al ATP para mantener las condiciones que apoyan la fotosíntesis y la longevidad de los cloroplastos.
Los cleptosomas digieren los cloroplastos para obtener nutrientes durante la inanición de las babosas, actuando como fuente de alimento.
Se encontraron mecanismos similares de retención y digestión de orgánulos en corales y anémonas, lo que indica una evolución convergente.

Conclusiones:

El descubrimiento de los cleptosomas proporciona un mecanismo para la 'fotosíntesis animal' en las babosas marinas.
Los cleptosomas son cruciales para la retención a largo plazo de los cloroplastos, la fotosíntesis y la adquisición de nutrientes.
La retención organellar de simbiontes fotosintéticos ha evolucionado de manera convergente en diversos linajes animales, destacando una estrategia compartida para aprovechar la energía solar.

Palabras clave:

Biología celular La endosimbiosis La evolución cleptoplastia canales iónicos orgánulos Animales fotosintéticos

Más Videos Relacionados

Studying Protein Import into Chloroplasts Using Protoplasts

Studying Protein Import into Chloroplasts Using Protoplasts

Published on: December 10, 2018

Isolation of Physiologically Active Thylakoids and Their Use in Energy-Dependent Protein Transport Assays

Isolation of Physiologically Active Thylakoids and Their Use in Energy-Dependent Protein Transport Assays

Published on: September 28, 2018

Videos de Conceptos Relacionados

The Anatomy of Chloroplasts

The Anatomy of Chloroplasts

Green algae and plants, including green stems and unripe fruit, harbor specialized organelles called chloroplasts to carry out photosynthesis. They coordinate both stages of photosynthesis — the light-dependent reactions and the light-independent reactions. The light-dependent reactions use sunlight to release oxygen and produce chemical energy in the form of ATP and NADPH, and the light-independent reactions capture CO2 and use ATP and NADPH to produce sugar.
Structure of...

Anatomy of Chloroplasts

Anatomy of Chloroplasts

Green algae and plants, including green stems and unripe fruit, harbor chloroplasts—the vital organelles where photosynthesis takes place. In plants, the highest density of chloroplasts is found in the mesophyll cells of leaves.

Protein Transport to the Inner Chloroplast Membrane

Protein Transport to the Inner Chloroplast Membrane

Proteins targeted to the inner chloroplast membrane, or plastid proteins, are transported by two general pathways: the stop-transfer and the re-insertion or post-import pathways. Most plastid proteins carry N-terminal transit sequences and internal import sequences targeting it to the specific chloroplast subcompartment. Proteins targeted by the stop-transfer pathway have internal hydrophobic sequences that inhibit their translocation into the stroma. As a result, these precursors are arrested...

Export of Mitochondrial and Chloroplast Genes

Export of Mitochondrial and Chloroplast Genes

A eukaryotic cell can have up to three different types of genetic systems: nuclear, mitochondrial, and chloroplast. During evolution, organelles have exported many genes to the nucleus; this transfer is still ongoing in some plant species. Approximately 18% of the Arabidopsis thaliana nuclear genome is thought to be derived from the chloroplast’s cyanobacterial ancestor, and around 75% of the yeast genome derived from the mitochondria’s bacterial ancestor. This export has occurred...

Protein Transport to the Stroma

Protein Transport to the Stroma

Chloroplasts are triple membrane structures with an outer membrane, an inner membrane, and a thylakoid membrane, each containing distinct metabolite transporters, membrane translocons, and enzymes. Appropriate sorting and translocating these proteins to their correct membrane systems is essential for chloroplast function.
Protein complexes called the translocon of the outer chloroplast membrane or TOC complex, and the translocon of the inner chloroplast membrane or TIC complex mediate the...

Photosystems

Photosystems

Photosystems are multiprotein complexes that form the functional units of photosynthesis in plants, algae, and cyanobacteria. They are found embedded in the membrane of tiny sac-like structures called thylakoids placed inside the chloroplast.
Functioning of Photosystems
Photosystems contain many pigment molecules, such as chlorophylls and carotenoids, arranged in a particular organization across two domains — the antenna complex and the reaction center. The main aim of the pigment...