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Transcytosis
Transcytosis (also known as cytopempsis) is a type of transcellular transport in which various macromolecules are transported across the interior of a cell. Macromolecules are captured in vesicles on one side of the cell, drawn across the cell, and ejected on the other side. Examples of macromolecules transported include IgA, transferrin, and insulin. While transcytosis is most commonly observed in epithelial cells, the process is also present elsewhere. Blood capillaries are a well-known site for transcytosis, though it occurs in other cells, including neurons, osteoclasts and M cells of the intestine. Regulation The regulation of transcytosis varies greatly due to the many different tissues in which this process is observed. Various tissue-specific mechanisms of transcytosis have been identified. Brefeldin A, a commonly used inhibitor of ER-to-Golgi apparatus transport, has been shown to inhibit transcytosis in dog kidney cells, which provided the first clues as to the nature o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcellular Transport
Transcellular transport involves the transportation of solutes by a cell ''through'' a cell. Transcellular transport can occur in three different ways active transport, passive transport, and transcytosis. Active Transport Main article: Active transport Active transport is the process of moving molecules from an area of low concentrations to an area of high concentration. There are two types of active transport, primary active transport and secondary active transport. Primary active transport uses adenosine triphosphate (ATP) to move specific molecules and solutes against its concentration gradient. Examples of molecules that follow this process are potassium K+, sodium Na+, and calcium Ca2+. A place in the human body where this occurs is in the intestines with the uptake of glucose. Secondary active transport is when one solute moves down the electrochemical gradient to produce enough energy to force the transport of another solute from low concentration to high concentration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RAB11A
Ras-related protein Rab-11A is a protein that in humans is encoded by the ''RAB11A'' gene. Function The protein encoded by this gene belongs to the small GTPase superfamily, Rab family. It is associated with both constitutive and regulated secretory pathways, and may be involved in protein transport. Rab-11a controls intracellular trafficking of the innate immune receptor TLR4, and thereby also receptor signaling Interactions RAB11A has been shown to interact with: * RAB11FIP1, * RAB11FIP2, * RAB11FIP3, * RAB11FIP4, and * RAB11FIP5 *Moesin Moesin is a protein that in humans is encoded by the ''MSN'' gene. Moesin (for membrane-organizing extension spike protein) is a member of the ERM protein family which includes ezrin and radixin. ERM proteins appear to function as cross-linkers ... References Further reading * * * * * * * * * * * * * * * * * {{PDB Gallery, geneid=8766 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid Epithelial Cell
Thyroid follicular cells (also called thyroid epithelial cells or thyrocytes) are the major cell type in the thyroid gland, and are responsible for the production and secretion of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). They form the single layer of cuboidal epithelium that makes up the outer structure of the almost spherical thyroid follicle. Structure Location Thyroid follicular cells form a simple cuboidal epithelium and are arranged in spherical thyroid follicles surrounding a fluid filled space known as the colloid. The interior space formed by the follicular cells is known as the follicular lumen. The basolateral membrane of follicular cells contains thyrotropin receptors which bind to thyroid-stimulating hormone (TSH) found circulating in the blood. Calcitonin-producing parafollicular cells are also found along the basement membrane of the thyroid follicle, interspersed between follicular cells; and in spaces between the spherical follicles. Para ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormones triiodothyronine (T3) and thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the metabolic rate and protein synthesis, and in children, growth and development. Calcitonin plays a role in calcium homeostasis. Secretion of the two thyroid hormones is regulated by thyroid-stimulating hormone (TSH), which is secreted from the anterior pituitary gland. TSH is regula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pregnancy (mammals)
In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female's uterus, and ends once it leaves the uterus. Fertilization and implantation During copulation, the male inseminates the female. The spermatozoon fertilizes an ovum or various ova in the uterus or fallopian tubes, and this results in one or multiple zygotes. Sometimes, a zygote can be created by humans outside of the animal's body in the artificial process of in-vitro fertilization. After fertilization, the newly formed zygote then begins to divide through mitosis, forming an embryo, which implants in the female's endometrium. At this time, the embryo usually consists of 50 cells. Development After implantation A blastocele is a small cavity on the center of the embryo, and the developing embryonary cells will grow around it. Then, a flat layer cell fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammary Gland
A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word ''mamma'', "breast". The mammary glands are arranged in organs such as the breasts in primates (for example, humans and chimpanzees), the udder in ruminants (for example, cows, goats, sheep, and deer), and the dugs of other animals (for example, dogs and cats). Lactorrhea, the occasional production of milk by the glands, can occur in any mammal, but in most mammals, lactation, the production of enough milk for nursing, occurs only in phenotypic females who have gestated in recent months or years. It is directed by hormonal guidance from sex steroids. In a few mammalian species, male lactation can occur. With humans, male lactation can occur only under specific circumstances. Mammals are divided into 3 groups: prototherians, metatherians, and eutherians. In the case of prototherians, both males and females have functional m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prolactin
Prolactin (PRL), also known as lactotropin, is a protein best known for its role in enabling mammals to produce milk. It is influential in over 300 separate processes in various vertebrates, including humans. Prolactin is secreted from the pituitary gland in response to eating, mating, estrogen treatment, ovulation and nursing. It is secreted heavily in pulses in between these events. Prolactin plays an essential role in metabolism, regulation of the immune system and pancreatic development. Discovered in non-human animals around 1930 by Oscar Riddle and confirmed in humans in 1970 by Henry Friesen, prolactin is a peptide hormone, encoded by the ''PRL'' gene. In mammals, prolactin is associated with milk production; in fish it is thought to be related to the control of water and salt balance. Prolactin also acts in a cytokine-like manner and as an important regulator of the immune system. It has important cell cycle-related functions as a growth-, differentiating- and ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estradiol
Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development of female secondary sexual characteristics such as the breasts, widening of the hips and a female-associated pattern of fat distribution. It is also important in the development and maintenance of female reproductive tissues such as the mammary glands, uterus and vagina during puberty, adulthood and pregnancy. It also has important effects in many other tissues including bone, fat, skin, liver, and the brain. Though estradiol levels in males are much lower than in females, estradiol has important roles in males as well. Apart from humans and other mammals, estradiol is also found in most vertebrates and crustaceans, insects, fish, and other animal species. Estradiol is produced especially within the follicles of the ovaries, but al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progesterone
Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the major progestogen in the body. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroids, including the sex hormones and the corticosteroids, and plays an important role in brain function as a neurosteroid. In addition to its role as a natural hormone, progesterone is also used as a medication, such as in combination with estrogen for contraception, to reduce the risk of uterine or cervical cancer, in hormone replacement therapy, and in feminizing hormone therapy. It was first prescribed in 1934. Biological activity Progesterone is the most important progestogen in the body. As a potent agonist of the nuclear progesterone receptor (nPR) (wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAPK1
Mitogen-activated protein kinase 1, (MAPK 1), also known as ERK2, is an enzyme that in humans is encoded by the ''MAPK1'' gene. Function The protein encoded by this gene is a member of the MAP kinase family. MAP kinases, also known as extracellular signal-regulated kinases (ERKs), act as an integration point for multiple biochemical signals, and are involved in a wide variety of cellular processes such as proliferation, differentiation, transcription regulation and development. The activation of this kinase requires its phosphorylation by upstream kinases. Upon activation, this kinase translocates to the nucleus of the stimulated cells, where it phosphorylates nuclear targets. Two alternatively spliced transcript variants encoding the same protein, but differing in the UTRs, have been reported for this gene. MAPK1 contains multiple amino acid sites that are phosphorylated and ubiquitinated. Model organisms Model organisms have been used in the study of MAPK1 function. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YES1
Proto-oncogene tyrosine-protein kinase Yes is a non-receptor tyrosine kinase that in humans is encoded by the ''YES1'' gene. This gene is the cellular homolog of the Yamaguchi sarcoma virus oncogene. The encoded protein has tyrosine kinase activity and belongs to the src family. This gene lies in close proximity to thymidylate synthase gene on chromosome 18, and a corresponding pseudogene has been found on chromosome 22. Interactions YES1 has been shown to interact with Janus kinase 2, CTNND1, RPL10 and Occludin Occludin is an enzyme ( EC 1.6) that oxidizes NADH. It was first identified in epithelial cells as a 65 kDa integral plasma-membrane protein localized at the tight junctions. Together with Claudins, and zonula occludens-1 (ZO-1), occludin has be .... References Further reading * * * * * * * * * * * * * * * * External links * {{gene-18-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
