Anti c-Fos Antibodies

c-Fos is a member of the Fos protein family and functions as a transcription factor. Localized primarily in the nucleus, it forms heterodimers with partner proteins such as c-Jun. These complexes bind to promoter regions and regulate the expression of target genes. The c-Fos gene is well-known as an “immediate early gene” because it is among the first genes to be induced in response to cellular stimulation. It is thought to play a key role in initiating stimulus-dependent changes to gene expression.

In neuroscience, c-Fos is widely used as a marker of neuronal activity. Previous studies have shown that c-Fos expression is rapidly induced following neuronal stimulation, with mRNA levels peaking within about 30 minutes. Protein levels subsequently peak 60–90 minutes after stimulation and remain elevated for roughly 2–5 hours¹⁾. Although the target genes regulated by c-Fos in neurons have not yet been fully characterized, c-Fos/Jun binding sites are found in the promoters of many neuropeptide and neurotransmitter-synthesizing enzyme genes, implicating c-Fos in the control of their expression.

“Anti c-Fos, Guinea Pig” is a polyclonal antibody against c-Fos raised in guinea pigs. It can be used to detect neuronal activity by immunohistochemistry. This guinea pig-derived antibody is compatible with multiplex staining alongside rabbit- or mouse-derived antibodies.

Antibody Information

Clonality	Polyclonal
Antigen	Synthetic peptide (N-terminus of c-Fos)
Host	Guinea Pig
Formulation	PBS, 1% Trehalose, 0.05% Sodium azide
Conjugate	Unconjugated
Cross-reactivity	Mouse
Application	Immunohistochemistry (Frozen section) 1:500-2,000

Application Data

Immunohistochemistry

＞Comparison of c-Fos expression after lipopolysaccharide (LPS) administration

[Result]
No c-Fos-positive cells were observed without LPS stimulation, whereas numerous c-Fos-positive cells appeared 2 hours after LPS administration. Because much of the c-Fos signal colocalized with Nissl-positive cell bodies, c-Fos was confirmed to be expressed in neurons.

＞Time course of c-Fos expression under osmotic stimulation

[Result]
Numerous c-Fos-positive cells were observed 2 hours after NaCl stimulation, whereas almost none remained positive at 7 hours—confirming the brief, transient expression pattern characteristic of c-Fos.

＞Comparison with Competitors’ Products

Data by courtesy of Dr. Furube, Department of Functional Anatomy and Neuroscience, Asahikawa Medical University

[Result]
This antibody produced a detection pattern comparable to those of competitor’s rabbit-derived antibodies. It demonstrated higher detection sensitivity than competitor’s mouse-derived antibody.

1. Hoffman, G. E. et al.: Front. Neuroendocrinol., 14(3), 173(1993).
   c-Fos and related immediate early gene products as markers of activity in neuroendocrine systems