Gremlin (protein)

Gremlin is an inhibitor in the TGF beta signaling pathway.

Structure

Gremlin1, previously known as Drm, is a highly conserved 20.7-kDa, 184 amino acid glycoprotein part of the DAN family and is a cysteine knot-secreted protein. Gremlin1 was first identified in differential screening as a transcriptional down-regulated gene in v-mos-transformed rat embryonic fibroblasts.

Function

Gremlin1 (Grem1) is known for its antagonistic interaction with bone morphogenetic proteins (BMPs) in the TGF beta signaling pathway. Grem1 inhibits predominantly BMP2 and BMP4 in limb buds and functions as part of a self-regulatory feedback signaling system, which is essential for normal limb bud development and digit formation. Inhibition of BMPs by Grem1 in limb buds allows the transcriptional up-regulation of the fibroblast growth factors (FGFs) 4 and 8 and Sonic hedgehog (SHH) ligands, which are part of the signaling system that controls progression of limb bud development. Grem1 regulation of BMP4 in mice embryos is also essential for kidney and lung branching morphogenesis.

Gremlin

A gremlin is a creature commonly depicted as mischievous and mechanically oriented, with a specific interest in aircraft. Gremlins' mischievous natures are similar to those of English folkloric imps, while their inclination to damage or dismantle machinery is more modern.

Origins in aviation

Although their origin is found in myths among airmen, claiming that the gremlins were responsible for sabotaging aircraft, John W. Hazen states that "some people" derive the name from the Old English word gremian, "to vex". While Carol Rose, in her book Spirits, Fairies, Leprechauns, and Goblins attributes the name to a combination of the name of Grimm's Fairy Tales, and Fremlin Beer. Since World War II, different fantastical creatures have been referred to as gremlins, bearing varying degrees of resemblance to the originals.

The term "gremlin" denoting a mischievous creature that sabotages aircraft, originates in Royal Air Force (RAF) slang in the 1920s among the British pilots stationed in Malta, the Middle East, and India, with the earliest recorded printed use being in a poem published in the journal Aeroplane in Malta on 10 April 1929. Later sources have sometimes claimed that the concept goes back to World War I, but there is no print evidence of this.

Kasakela Chimpanzee Community

The Kasakela chimpanzee community is a habituated community of wild eastern chimpanzees that lives in Gombe National Park near Lake Tanganyika in Tanzania. The community was the subject of Dr Jane Goodall's pioneering study that began in 1960, and studies have continued ever since. As a result, the community has been instrumental in the study of chimpanzees, and has been popularized in several books and documentaries. The community's popularity was enhanced by Dr Goodall's practice of giving names to the chimpanzees she was observing, in contrast to the typical scientific practice of identifying the subjects by number. Dr Goodall generally used a naming convention in which infants were given names starting with the same letter as their mother, allowing the recognition of matrilineal lines.

AMC Gremlin

The AMC Gremlin is an American subcompact automobile introduced in 1970 engineered and manufactured and marketed in a single, two-door body style in America (1970-1978) by American Motors Corporation (AMC) — as well as in Mexico (1974-1978) by AMC's Vehículos Automotores Mexicanos (VAM) subsidiary.

Featuring a shortened Hornet platform and bodywork with a pronounced, almost vertical, hatchback tail, the Gremlin was classified an economy car by 1970s U.S. standards and competed with the Chevrolet Vega and Ford Pinto, as well as imported cars that included the Volkswagen Beetle and Toyota Corona. The small domestic automaker marketed the Gremlin as "the first American-built import".

The Gremlin reached a total production of 671,475 over a single generation — and was superseded by a restyled variant, the AMC Spirit.

History

Origin and design

The idea for the Gremlin began in 1966 when design chief at American Motors, Richard A. Teague, and stylist Bob Nixon discussed the possibility of a shortened version of AMC's compact car. On an airline flight, Teague's solution, which he said he sketched on an air sickness bag, was to truncate the tail of a Javelin. Bob Nixon joined AMC as a 23-year-old and did the first formal design sketches in 1967 for the car that was to be the Gremlin.