Microinjection

Microinjection refers to the process of using a micro needle to insert substances at a microscopic or borderline macroscopic level into a single living cell. It is a simple mechanical process in which an extremely fine micro needle penetrates the cell membrane and sometimes the nuclear envelope and releases its contents. Microinjection is normally performed under a specialized optical microscope setup called a micromanipulator. The process is frequently used as a vector in genetic engineering and transgenetics to insert genetic material into a single cell. The process of cloning also involves microinjections.

Examples

 * Scientists can create simple transgenic organisms by injecting genes into the testicle of a nematode at a point were the cells that will become its sperm are undergoing meiosis. Since the developing gametes share a common cytoplasm, all of the nematode's gametes will carry a foreign gene as the result of a single injection.


 * Microinjection is used as a vector in transgenic plant production.


 * Microinjection of genes into fertilized eggs is a common vector used in the production of higher forms of transgenic animals.


 * Microinjection of a gene knockdown reagent such as a Morpholino oligo into eggs or early zygotes is commonly used to probe the function of a gene during development of embryos.