Related Experiment Video
Updated: Jun 18, 2025
10:00
High-throughput Quantitative Real-time RT-PCR Assay for Determining Expression Profiles of Types I and III Interferon Subtypes
Published on: March 24, 2015
13.4K
Evolutionary insights of interferon lambda genes in tetrapods.
Devika Gautam1,2, Anil Sindhu2, Ashutosh Vats1
1Animal Genomics Lab, Animal Biotechnology Centre, ICAR-National Dairy Research Institute (NDRI), Karnal, Haryana, India.
Journal of Evolutionary Biology
|July 27, 2024
Summary
Type III interferons (IFN-λ) are key antiviral proteins. Evolutionary analysis reveals significant gene diversity and copy number variations in tetrapods, highlighting their conserved function.
Area of Science:
- Immunology
- Evolutionary Biology
- Genetics
Background:
- Type III interferon (IFN-λ) is a crucial innate antiviral protein.
- Understanding the evolutionary dynamics of IFN-λ and its receptors is vital for comprehending host defense mechanisms.
Purpose of the Study:
- To investigate the evolutionary diversity of Type III interferon (IFN-λ) genes and their receptors across 42 tetrapod species.
- To analyze copy number variation (CNV) of IFN-λ in Indian cattle and buffalo.
Main Methods:
- Computational evolutionary analysis of IFN-λ and receptor sequences from 42 tetrapod species.
- Quantitative Polymerase Chain Reaction (qPCR) for determining IFN-λ copy number variation in cattle and buffalo.
Main Results:
- Tetrapod IFN-λ genes are predominantly intron-containing, with variations in locus numbers (1-2) across different groups (reptiles, mammals, birds, marsupials, monotremes).
- Placental mammals and amphibians show multiple IFN-λ genes, including intron-less forms; IFN-λ4 is an ancestral mammalian form.
- Purifying selection maintains IFN-λ function; gene expansion in amphibians and camels, and CNV in Indian buffalo and cattle breeds (IFN-λ3 and IFN-λ4) were observed.
Conclusions:
- IFN-λ exhibits significant evolutionary diversity in tetrapods, with conserved synteny for intron-less IFN-λ1 and receptors.
- Despite the presence of Type I IFNs, IFN-λ has retained its essential biological functions.
- Gene duplication and conversion contribute to IFN-λ CNV, underscoring its dynamic evolution and importance in innate immunity.
Related Concept Videos
02:32Exon Recombination
3.6K
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...
Exon shuffling follows “splice frame rules.” Each exon...
3.6K
03:08LTR Retrotransposons
17.4K
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
17.4K
02:37Gene Duplication and Divergence
6.1K
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...
6.1K
02:05Gene Evolution - Fast or Slow?
7.1K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
In contrast, regions which code...
7.1K
01:54Convergent Evolution
27.7K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
27.7K
03:18Non-LTR Retrotransposons
11.4K
As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...
11.4K