Organelle biogenesis is the

biogenesis Spontaneous generation is a superseded scientific theory that held that living creatures could arise from nonliving matter and that such processes were commonplace and regular. It was hypothesized that certain forms, such as fleas, could arise fr ...

, or creation, of

cellular organelles In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the ...

cells Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery w ...

. Organelle biogenesis includes the process by which cellular organelles are split between daughter cells during

mitosis In cell biology, mitosis () is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is mainta ...

; this process is called organelle inheritance.

Discovery

Following the discovery of cellular organelles in the nineteenth century, little was known about their function and

synthesis Synthesis or synthesize may refer to: Science Chemistry and biochemistry *Chemical synthesis, the execution of chemical reactions to form a more complex molecule from chemical precursors ** Organic synthesis, the chemical synthesis of organ ...

until the development of

electron microscopy An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a hi ...

and

subcellular fractionation In cell biology, cell fractionation is the process used to separate cellular components while preserving individual functions of each component. This is a method that was originally used to demonstrate the cellular location of various biochemical ...

in the twentieth century. This allowed experiments on the function, structure, and biogenesis of these organelles to commence. Mechanisms of

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

sorting and retrieval have been found to give organelles their characteristic

composition Composition or Compositions may refer to: Arts and literature *Composition (dance), practice and teaching of choreography *Composition (language), in literature and rhetoric, producing a work in spoken tradition and written discourse, to include v ...

. It is known that cellular organelles can come from preexisting organelles; however, it is a subject of controversy whether organelles can be created without a preexisting one.

Process

Several processes are known to have developed for organelle biogenesis. These can range from

de novo synthesis In chemistry, ''de novo'' synthesis () refers to the synthesis of complex molecules from simple molecules such as sugars or amino acids, as opposed to recycling after partial degradation. For example, nucleotides are not needed in the diet as the ...

to the copying of a template organelle; the formation of an organelle 'from scratch' and using a preexisting organelle as a template to manufacture an organelle, respectively. The distinct structures of each organelle are thought to be caused by the different mechanisms of the processes which create them and the proteins that they are made up of. Organelles may also be 'split' between two cells during the process of cellular division (known as organelle inheritance), where the organelle of the parent cell doubles in size and then splits with each half being delivered to their respective daughter cells. The process of organelle biogenesis is known to be regulated by specialized transcription networks that modulate the expression of the

genes In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

that code for specific organellar proteins. In order for organelle biogenesis to be carried out properly, the specific genes coding for the organellar proteins must be transcribed properly and the translation of the resulting

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is ...

must be successful. In addition to this, the process requires the transfer of

polypeptides Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A p ...

to their site of function, guided by signaling

peptides Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A p ...

. If proteins are not directed to their respective sites of subcellular function, a defective organelle that fails to fulfill its tasks within the cell properly may result. Several metabolic diseases are known to be caused by a fault in the process of organelle biogenesis. These may include mitochondrial biogenesis defects,

peroxisome A peroxisome () is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells. Peroxisomes are oxidative organelles. Frequently, molecular oxygen serves as a co-substrate, from which hydrogen pero ...

biogenesis disorders, and

lysosomal A lysosome () is a membrane-bound organelle found in many animal Cell (biology), cells. They are spherical Vesicle (biology and chemistry), vesicles that contain Hydrolysis, hydrolytic enzymes that can break down many kinds of biomolecules. A ly ...

storage disorders.

References

{{reflist Biochemistry Cell biology Organelles