Video Experimental Relacionado
Updated: Apr 28, 2026
08:19
Quantitative Comparison of cis-Regulatory Element CRE Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
11.3K
La evolución de la regulación génica subyace a una diferencia morfológica entre dos especies hermanas de Drosophila
Sangyun Jeong1, Mark Rebeiz, Peter Andolfatto
1Howard Hughes Medical Institute and Laboratory of Molecular Biology, University of Wisconsin, 1525 Linden Drive, Madison, WI 53706, USA.
Cell
|March 11, 2008
Resumen
Los cambios evolutivos en la pigmentación corporal entre las especies de Drosophila son impulsados por mutaciones en los elementos reguladores de genes. Específicamente, la pérdida de pigmentación en D. santomea se debió a la inactivación del elemento regulador del bronceado.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Genética La genética.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La divergencia morfológica entre especies es un área clave de la biología evolutiva.
- Comprender la base genética de rasgos como la pigmentación corporal es crucial para los estudios evolutivos.
Objetivo del estudio:
- Investigar los mecanismos genéticos y moleculares detrás de la divergencia de los patrones de pigmentación corporal en Drosophila yakuba y Drosophila santomea.
- Identificar los cambios genéticos específicos responsables de la pérdida de pigmentación en D. santomea.
Principales métodos:
- Análisis genético comparativo de D. yakuba y D. santomea.
- Examen de los patrones de expresión génica para los genes de pigmentación, específicamente "bronceado" y "amarillo".
- Identificación y caracterización de mutaciones dentro de los elementos cis-reguladores (CREs) del gen "bronceado".
Principales resultados:
- La pérdida de pigmentación corporal en D. santomea está asociada con la pérdida selectiva de expresión de los genes de pigmentación "bronceado" y "amarillo".
- La expresión del gen "bronceado" fue eliminada debido a mutaciones en un elemento cis-regulador específico (CRE), mientras que la secuencia proteica se mantuvo intacta.
- Se identificaron tres alelos independientes de pérdida de función del CRE "bronceado" en el linaje de D. santomea.
Conclusiones:
- Los cambios evolutivos funcionales en genes con múltiples efectos (loci pleiotrópicos) a menudo surgen de mutaciones en sus elementos cis-reguladores.
- El estudio proporciona evidencia empírica que apoya la hipótesis de que los CREs modulares son puntos calientes para la innovación evolutiva que conduce a la divergencia morfológica.
Videos de Conceptos Relacionados
02:32Position-effect Variegation
5.6K
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
5.6K
02:02Cis-regulatory Sequences
9.4K
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
9.4K
02:27Background and Environment Affect Phenotype
5.8K
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
5.8K
02:45The Ratio of X Chromosome to Autosomes
11.5K
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female...
11.5K
02:50Dosage Compensation
6.3K
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will...
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will...
6.3K
02:37Gene Duplication and Divergence
6.8K
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...
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...
6.8K