Home Science Biology Cells, Organs & Tissues Alternate titles: RER, rough ER Show rough endoplasmic reticulum (RER), series of connected flattened sacs, part of a continuous membrane organelle within the
cytoplasm of eukaryotic cells, that plays a central role in the synthesis of proteins. The rough endoplasmic reticulum (RER) is so named for the appearance of its outer
surface, which is studded with protein-synthesizing particles known as ribosomes. This feature distinguishes it superficially and functionally from the other major type of endoplasmic reticulum (ER), the
smooth endoplasmic reticulum (SER), which lacks ribosomes and is involved in the synthesis and storage of lipids. RER occurs in both animal and plant cells. The RER membrane is continuous with the nuclear envelope, which surrounds the cell nucleus. The RER is also located near the Golgi apparatus, which transports, modifies, and packages proteins for delivery to targeted
destinations. Many proteins that are synthesized in the RER are packaged into vesicles and transported to the Golgi apparatus. Read More on This Topic cell: The rough endoplasmic reticulum The RER is generally a series of connected flattened sacs. It plays a central role in the synthesis and export of proteins and glycoproteins... Protein synthesis begins in the cytosol with a process known as translation, in which the protein is assembled from an RNA sequence. As the protein grows, if it contains a signal sequence at its amino-terminal end, it will become bound to a signal recognition particle, which carries the ribosome to the RER membrane. Once bound to the RER, the signal recognition particle dissociates, and protein translation continues. The newly formed protein then either becomes embedded in the RER membrane, in the case of a transmembrane protein, or is transmitted into the RER lumen via a translocon channel, in the case of a water-soluble protein. In the RER lumen, proteins may undergo slight modifications, such as having their signal sequences cleaved or undergoing glycosylation (in which an oligosaccharide is added, producing a glycoprotein). Protein form also changes, whereby the molecule assumes its three-dimensional conformation. From the RER, proteins move into a transitional region of the ER lumen, which is largely lacking in ribosomes. Some proteins, such as secretory proteins, which are released by cells, are packaged in vesicles and move to the Golgi apparatus. Other proteins remain in the ER, where they carry out their specified functions. Abnormalities in RER structure and function are associated with certain types of disease in humans. In particular, the accumulation in the RER of misfolded proteins, which normally are returned to the cytosol, where they are degraded, can result in ER stress, leading to cell dysfunction and cell death. For example, the accumulation of misfolded collagen proteins in the RER, owing to mutations in collagen-encoding genes, underlies various inherited skeletal disorders, including spondyloepimetaphyseal dysplasia, which is characterized by abnormal bone growth, weak joints, and susceptibility to joint dislocation. Kara Rogers
What object can represent the rough ER?Rough ER transports materials through the cell and produces proteins in sacks called cisternae (which are sent to the Golgi body, or inserted into the cell membrane). It is represented by sour gummy worms.
What everyday object is like a rough endoplasmic reticulum?The floors or walkways of the kitchen are like the endoplasmic reticulum, because people have to walk on them to get around the kitchen. Lysosomes are like garbage cans or garbage disposals because materials are put and broken down in them.
What would the rough ER be in a house?The Endoplasmic Reticulum is the pathway of the cell, sort of like a hallway of a home. The Rough ER has ribosomes studded on it. It can be compared to a hallway with different rooms branching off of it.
What are endoplasmic reticulum similar to in real life?The endoplasmic reticulum is like the highway system because the cell uses the endoplasmic reticulum to move material throughout the cell like people use highways to move throughout the country.
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