Related Experiment Video

Updated: Aug 17, 2026

Peptide-based Identification of Functional Motifs and their Binding Partners
14:28

Peptide-based Identification of Functional Motifs and their Binding Partners

Published on: June 30, 2013

Endogenous retroviral envelope peptide expression is involved in a regulation of lymphocyte and hematopoietic

I V Chernukhin1, S K Khaldoyanidi, K V Gaidul

  • 1Institute of Clinical Immunology, Siberian Branch, Russian Academy of Medical Sciences, Novosibirsk.

Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie
|January 1, 1995
PubMed

Insights

Endogenous MuLV p15E-related proteins in mice regulate hematopoietic stem cell activity. These peptides inhibit lymphocyte and granulocyte-macrophage precursors while stimulating erythroid colony growth.

Area of Science:

  • Immunology
  • Hematology
  • Molecular Biology

Background:

  • Endogenous retroviral proteins, such as MuLV p15E, play roles in cellular functions.
  • The immunosuppressive domain (ISD) of MuLV p15E is known to affect immune responses.
  • Hematopoietic precursor activity is crucial for blood cell formation and regulation.

Purpose of the Study:

  • To investigate the biological function of endogenously expressed MuLV p15E-related proteins in mice.
  • To determine the role of these proteins in lymphocyte and hematopoietic precursor activity.
  • To examine the effects of phenylhydrazine (PHZ)-induced hemolytic anemia on p15E-related peptide expression.

Main Methods:

  • Spleen cells from PHZ-treated mice were cultured.
  • Hyperimmune rabbit antisera against the ISD of MuLV p15E were used for detection.
  • Conditioned medium (PHZ/CM) was analyzed for its effects on lymphocyte blastogenesis and hematopoietic precursor activity.
  • Antibodies against ISD/p15E were used to abrogate observed effects.

Main Results:

  • High levels of endogenous p15E-related peptides were detected in spleen cells of PHZ-treated mice.
  • PHZ/CM inhibited lymphocyte blastogenesis and granulocyte-macrophage (GM) precursor activity.
  • PHZ/CM stimulated erythroid colony growth.
  • Anti-ISD/p15E antibodies neutralized the effects of PHZ/CM.
  • Antibodies bound to 14K and 48K structural peptides in PHZ/CM.

Conclusions:

  • Erythroid immature cells produce and release p15E-related proteins into the cell culture medium.
  • These endogenous peptides exhibit MuLV p15E-like properties, down-regulating lymphocyte and GM precursor activities.
  • The identified peptides promote colony growth in the erythroid compartment, suggesting a regulatory role in hematopoiesis.

More Related Videos

Retroviral Infection of Murine Embryonic Stem Cell Derived Embryoid Body Cells for Analysis of Hematopoietic Differentiation11:40

Retroviral Infection of Murine Embryonic Stem Cell Derived Embryoid Body Cells for Analysis of Hematopoietic Differentiation

Published on: October 20, 2014

Retroviral Scanning: Mapping MLV Integration Sites to Define Cell-specific Regulatory Regions10:10

Retroviral Scanning: Mapping MLV Integration Sites to Define Cell-specific Regulatory Regions

Published on: May 28, 2017

Related Concept Videos

Retrovirus Life Cycles01:10

Retrovirus Life Cycles

Retroviruses have a single-stranded RNA genome that undergoes a special form of replication. Once the retrovirus has entered the host cell, an enzyme called reverse transcriptase synthesizes double-stranded DNA from the retroviral RNA genome. This DNA copy of the genome is then integrated into the host’s genome inside the nucleus via an enzyme called integrase. Consequently, the retroviral genome is transcribed into RNA whenever the host’s genome is transcribed, allowing the retrovirus to...
Retroviruses02:33

Retroviruses

Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
LTR Retrotransposons03:08

LTR Retrotransposons

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...
Regulation of Nuclear Protein Sorting01:45

Regulation of Nuclear Protein Sorting

Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
Receptor Downregulation in MVBs01:15

Receptor Downregulation in MVBs

Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that  lead to cell proliferation, migration, and differentiation. Overexpression of EGFR  stimulates cells to proliferate. Excessive  EGFR activation may...
Regulation of Hematopoietic Stem Cells01:01

Regulation of Hematopoietic Stem Cells

All blood and immune cells are produced from the multipotent hematopoietic stem cells (HSCs) by the process of hematopoiesis. However, they all have a limited life span. In addition, many are depleted in immune surveillance or combatting an injury or infection. This makes blood one of the most regenerative tissues. Hematopoiesis helps replenish these blood and immune cells, restoring the body's normal functioning. However, overproduction of blood and immune cells can make them cancerous or...