Cip1-interacting zinc finger protein is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
that in humans is encoded by the ''CIZ1''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Function
The protein encoded by this gene is a
zinc finger
A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a ...
DNA binding
transcription factor
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding t ...
that interacts with CIP1 (
p21 / CDKN1A), part of a complex with
cyclin E
Cyclin E is a member of the cyclin family.
Cyclin E binds to G1 phase Cdk2, which is required for the transition from G1 to S phase of the cell cycle that determines initiation of DNA duplication. The Cyclin E/CDK2 complex phosphorylates p27 ...
. The encoded protein may regulate the cellular localization of CIP1.
Clinical significance
An altered circulating form of the Ciz1 protein is synthesized by
lung cancer
Lung cancer, also known as lung carcinoma, is a malignant tumor that begins in the lung. Lung cancer is caused by genetic damage to the DNA of cells in the airways, often caused by cigarette smoking or inhaling damaging chemicals. Damaged ...
cells, even when they are at a very early stage. Hence detection of this protein variant in blood could be used as a
biomarker
In biomedical contexts, a biomarker, or biological marker, is a measurable indicator of some biological state or condition. Biomarkers are often measured and evaluated using blood, urine, or soft tissues to examine normal biological processes, ...
for early detection of lung cancer.
''Ciz1'' mutant mice
Aged (18-mo-old) ''Ciz1
-/-'' mice have increased neuronal
DNA double-strand breaks that likely contributed to their loss of neurons and cognitive decline with age.
Embryonic fibroblasts from ''Ciz1
-/-'' mice show abnormal sensitivity to
γ-irradiation with persistent DNA breaks, aberrant
cell cycle
The cell cycle, or cell-division cycle, is the sequential series of events that take place in a cell (biology), cell that causes it to divide into two daughter cells. These events include the growth of the cell, duplication of its DNA (DNA re ...
progression and increased
apoptosis
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
.
Interactions
CIZ1 has been shown to
interact with
P21.
References
External links
*
Further reading
*
*
*
*
*
*
*
{{gene-9-stub