Related Experiment Videos
Expression of mink cell focus-forming murine leukemia virus-related transcripts in AKR mice
Abstract:
We used a synthetic 16-base-pair mink cell focus-forming (MCF) env-specific oligomer as radiolabeled probe to study MCF murine leukemia virus (MuLV)-related transcripts in brain, kidney, liver, spleen, and thymus tissues of AKR mice ranging from 5 weeks to 6 months (mo) of age. Tissue-specific expression of poly (A) + RNAs was seen: 6.0-kilobase (kb) transcripts were detected in the liver and kidney; 7.2- and 1.8-kb RNA species were present in the thymus. In addition, all the tissues tested contained 3.0-kb messages. The transcription of these MCF-related mRNAs was independent of the presence of ecotropic and xenotropic MuLVs. In general, expression of the MCF env-related transcripts appeared to peak at 2 mo of age; these messages were barely detectable in brain, kidney, liver, and spleen tissues after 2 mo and in thymus tissue after 4 mo of age. All of the subgenomic MCF env-related mRNAs (6.0, 7.2, 1.8, and 3.0 kb) appeared to contain the 190-base-pair cellular DNA insert, characteristic of the long terminal repeats associated with endogenous MCF env-related proviruses (A. S. Khan and M. A. Martin, Proc. Natl. Acad. Sci. USA 80:2699-2703, 1983). No genomic-size (8.4-kb) transcripts corresponding to endogenous MCF-related proviruses were detected. An 8.4-kb MCF env-related mRNA was first seen at 3 mo of age, exclusively in thymus tissue. This species most likely represents the first appearance of a recombinant MCF-related MuLV genome. The transcripts which were detected in thymus tissue might be involved in the generation of leukemogenic MCF viruses.
Insights
This study investigated mink cell focus-forming (MCF) murine leukemia virus (MuLV)-related RNA transcripts in AKR mice. MCF env-related transcripts were detected, with expression peaking around 2 months of age and varying by tissue.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Murine leukemia viruses (MuLVs) are retroviruses implicated in various diseases in mice.
- Mink cell focus-forming (MCF) viruses are a specific type of MuLV known for their distinct envelope (env) gene.
- Understanding the expression patterns of MCF env-related transcripts is crucial for studying MuLV pathogenesis.
Purpose of the Study:
- To investigate the tissue-specific expression of MCF murine leukemia virus (MuLV)-related transcripts in AKR mice.
- To determine the age-dependent expression patterns of these transcripts.
- To explore the relationship between MCF env-related transcripts and endogenous proviruses.
Main Methods:
- Utilized a synthetic 16-base-pair MCF env-specific oligomer as a radiolabeled probe.
- Analyzed poly (A)+ RNA from brain, kidney, liver, spleen, and thymus tissues of AKR mice.
- Examined mice across a range of ages from 5 weeks to 6 months.
Main Results:
- Detected tissue-specific expression of MCF env-related transcripts (6.0, 7.2, 1.8, and 3.0 kb).
- Observed that transcription was independent of ecotropic and xenotropic MuLVs.
- Expression generally peaked at 2 months of age, decreasing significantly in most tissues thereafter.
- Identified an 8.4-kb MCF env-related mRNA exclusively in thymus tissue starting at 3 months, suggesting a recombinant MuLV genome.
Conclusions:
- MCF env-related transcripts exhibit distinct tissue and age-dependent expression patterns in AKR mice.
- The presence of a specific 8.4-kb transcript in thymus may indicate the emergence of leukemogenic MCF viruses.
- These findings contribute to understanding the molecular mechanisms underlying MuLV-related leukemogenesis.