Video Experimental Relacionado
Updated: Jul 9, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
La estructura de un pseudogén humano de alfa-globina y su relación con la duplicación del gen alfa-globina
Cell
|September 1, 1980
Resumen
Este estudio presenta la secuencia de nucleótidos de un pseudogén humano alfa-globina (psi alfa 1). El pseudogén contiene mutaciones que impiden la producción de proteínas y un empalme alterado, lo que sugiere que no es funcional.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- Los genes humanos de alfa-globina son cruciales para el transporte de oxígeno.
- Los pseudogenes son copias de genes no funcionales que pueden proporcionar información sobre la evolución de los genes.
- La comprensión de la formación de pseudogenes es clave para descifrar la evolución del genoma.
Objetivo del estudio:
- Determinar la secuencia completa de nucleótidos del pseudogén humano alfa-globina (psi alfa 1).
- Para comparar psi alfa 1 con los genes alfa-globina funcionales (alfa 1 y alfa 2).
- Para investigar la relación evolutiva de psi alfa 1 con los genes adyacentes de alfa-globina.
Principales métodos:
- Secuenciación de nucleótidos del pseudogén humano alfa-globina (psi alfa 1).
- Análisis comparativo de secuencias entre los genes psi alfa 1 y los genes alfa-globina humanos funcionales (alfa 1, alfa 2).
- Análisis de regiones flanqueantes y secuencias intermedias para elementos funcionales.
Principales resultados:
- psi alfa 1 contiene una mutación del codón iniciador y deleciones de desplazamiento de marco, lo que lo hace incapaz de producir un polipéptido alfa-globina.
- El pseudogén posee dos secuencias intermedias típicas de los genes de alfa-globina de los mamíferos, pero con señales de empalme alteradas o ausentes.
- psi alfa 1, alfa 1 y alfa 2 comparten una secuencia homóloga (GCCTGTGTGTGCCTG) flanqueando sus sitios de adición poli-A, lo que sugiere un papel en la duplicación de genes.
Conclusiones:
- El pseudogén humano de alfa-globina (psi alfa 1) no es funcional debido a mutaciones críticas y defectos de empalme.
- La presencia de secuencias intermedias características, a pesar de los defectos, apunta a su origen en un gen alfa-globina funcional.
- La secuencia homóloga que bordea las unidades de duplicación de genes alfa-globina puede haber facilitado el origen y la evolución de pseudogenes como psi alfa 1.
Videos de Conceptos Relacionados
02:07Organization of Genes
Overview
01:57Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
02:32Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
02:05Duplication of Chromatin Structure
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation.
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...