Invasion and Persistence of a Selfish Gene in the Cnidaria
نویسندگان
چکیده
BACKGROUND Homing endonuclease genes (HEGs) are superfluous, but are capable of invading populations that mix alleles by biasing their inheritance patterns through gene conversion. One model suggests that their long-term persistence is achieved through recurrent invasion. This circumvents evolutionary degeneration, but requires reasonable rates of transfer between species to maintain purifying selection. Although HEGs are found in a variety of microbes, we found the previous discovery of this type of selfish genetic element in the mitochondria of a sea anemone surprising. METHODS/PRINCIPAL FINDINGS We surveyed 29 species of Cnidaria for the presence of the COXI HEG. Statistical analyses provided evidence for HEG invasion. We also found that 96 individuals of Metridium senile, from five different locations in the UK, had identical HEG sequences. This lack of sequence divergence illustrates the stable nature of Anthozoan mitochondria. Our data suggests this HEG conforms to the recurrent invasion model of evolution. CONCLUSIONS Ordinarily such low rates of HEG transfer would likely be insufficient to enable major invasion. However, the slow rate of Anthozoan mitochondrial change lengthens greatly the time to HEG degeneration: this significantly extends the periodicity of the HEG life-cycle. We suggest that a combination of very low substitution rates and rare transfers facilitated metazoan HEG invasion.
منابع مشابه
Molecular and phylogenetic characterization of Thelohanellus boggoti Qadri, 1962 (Cnidaria, Myxosporea, Bivalvulida) infecting the fin of Indian minor carp Labeo dero (Hamilton, 1822)
A myxozoan parasite belonging to the genus Thelohanellus Kudo, 1933 (Cnidaria, Myxosporea, Bivalvulida) was isolated from the fins of Labeo dero inhabiting Ranjit Sagar Wetland, Punjab, India. The plasmodium was 0.5-0.7 mm in diameter each containing 80- 100 number of myxospores. Myxospores were egg shaped to ovoidal in valvular view having bluntly pointed anterior and broad rounded posterior e...
متن کاملThe Difference of Expression of 18 Genes in Axillary Invasion and Vascular Invasion Compared to Control Samples in Breast Cancer
Background & Objective: Recent studies from gene profiling have revealed some genes that are overexpressed in the epithelial-mesenchymal transition (EMT) process and are responsible for its initiation and activation resulting in tumor progression and metastasis. The present study aimed to assess the role of genes involved in the EMT process and the association of these genes wi...
متن کاملProbiotic Bifidobacterium Lactis Bacteria Inhibit the Invasion Phenotype of Shigella Dysenteriae Induced By Invasion Plasmid Antigen C
Background and Aims: Shigellosis is an acute gastroenteritis and Invasion plasmid antigen C (IpaC) is the first effector protein for Shigella invasion of intestinal cells. Among lactic acid bacteria, Bifidobacterium lactis (B. lactis) has received increasing attention for protection of a potential host against gastrointestinal infections. The aim of this study was to investigate the inhibitory ...
متن کاملN-myc downstream regulated gene 2 overexpression reduces matrix metalloproteinase-2 and -9 activities and cell invasion of A549 lung cancer cell line in vitro
Objective(s):N-myc downstream regulated gene 2 (NDRG2) is a candidate gene for tumor suppression. The expression of NDRG2 is down-regulated in several tumors including lung cancer. The aim of this study was to explore the effect of NDRG2 overexpression on invasion, migration, and enzymatic activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in human lung adenocarcinoma A549 cells. Ma...
متن کاملHyper eosinophilia associated with myeloid and lymphoid neoplasms
Eosinophilia in the absence of allergies, asthma, drug reactions, parasitic infections and connective tissue diseases can be eosinophilic clonal disorders, lymphoma or myeloproliferative disorders. Hypereosinophilia with the persistence of eosinophils ≥1500 /mm³ in blood or more than 20% of eosinophils in the bone marrow may be observed in many reactive or clonal disorders, the result of which ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- PLoS ONE
دوره 1 شماره
صفحات -
تاریخ انتشار 2006