Kinetoplast
Encyclopedia
A kinetoplast is a disk-shaped mass of circular DNA
inside a large mitochondrion
that contains many copies of the mitochondrial genome. Kinetoplasts are only found in protozoa
of the class Kinetoplastida. Kinetoplasts are usually adjacent to the organisms' flagellar
basal body
leading to the thought that they are tightly bound to the cytoskeleton
.
Trypanosomes, a group of flagellated protozoans have a kinetoplast contained inside one large mitochondrion. Trypanosoma brucei
, the parasite which causes African trypanosomiasis (African sleeping sickness), is an example of a trypanosome with a kinetoplast. Its kinetoplast is easily visible in samples stained with DAPI
, a fluorescent DNA stain.
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
inside a large mitochondrion
Mitochondrion
In cell biology, a mitochondrion is a membrane-enclosed organelle found in most eukaryotic cells. These organelles range from 0.5 to 1.0 micrometers in diameter...
that contains many copies of the mitochondrial genome. Kinetoplasts are only found in protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
of the class Kinetoplastida. Kinetoplasts are usually adjacent to the organisms' flagellar
Flagellum
A flagellum is a tail-like projection that protrudes from the cell body of certain prokaryotic and eukaryotic cells, and plays the dual role of locomotion and sense organ, being sensitive to chemicals and temperatures outside the cell. There are some notable differences between prokaryotic and...
basal body
Basal body
A basal body is an organelle formed from a centriole, and a short cylindrical array of microtubules. It is found at the base of a eukaryotic undulipodium and serves as a nucleation site for the growth of the axoneme microtubules...
leading to the thought that they are tightly bound to the cytoskeleton
Cytoskeleton
The cytoskeleton is a cellular "scaffolding" or "skeleton" contained within a cell's cytoplasm and is made out of protein. The cytoskeleton is present in all cells; it was once thought to be unique to eukaryotes, but recent research has identified the prokaryotic cytoskeleton...
.
Trypanosomes, a group of flagellated protozoans have a kinetoplast contained inside one large mitochondrion. Trypanosoma brucei
Trypanosoma brucei
Trypanosoma brucei is a parasitic protist species that causes African trypanosomiasis in humans and nagana in animals in Africa. There are 3 sub-species of T. brucei: T. b. brucei, T. b. gambiense and T. b. rhodesiense.These obligate parasites have two hosts - an insect vector and mammalian host...
, the parasite which causes African trypanosomiasis (African sleeping sickness), is an example of a trypanosome with a kinetoplast. Its kinetoplast is easily visible in samples stained with DAPI
DAPI
DAPI or 4',6-diamidino-2-phenylindole is a fluorescent stain that binds strongly to A-T rich regions in DNA. It is used extensively in fluorescence microscopy...
, a fluorescent DNA stain.