CREB

CREB (cAMP response element-binding protein) is a cellular transcription factor. It binds to certain DNA sequences called cAMP response elements (CRE), thereby increasing or decreasing the transcription of the downstream genes. CREB was first described in 1987 as a cAMP-responsive transcription factor regulating the somatostatin gene.

Genes whose transcription is regulated by CREB include: c-fos, BDNF, tyrosine hydroxylase, numerous neuropeptides (such as somatostatin, enkephalin, VGF, corticotropin-releasing hormone), and genes involved in the mammalian circadian clock (PER1, PER2).

CREB is closely related in structure and function to CREM (cAMP response element modulator) and ATF-1 (activating transcription factor-1) proteins. CREB proteins are expressed in many animals, including humans.

CREB has a well-documented role in neuronal plasticity and long-term memory formation in the brain and has been shown to be integral in the formation of spatial memory. CREB downregulation is implicated in the pathology of Alzheimer's disease and increasing the expression of CREB is being considered as a possible therapeutic target for Alzheimers disease. CREB also has a role in photoentrainment in mammals.

Siem Reap

Siem Reap (Khmer: ក្រុងសៀមរាប, pronounced [siəm riəp]; Thai: เสียมราฐ) is the capital city of Siem Reap Province in northwestern Cambodia, and a popular resort town as the gateway to Angkor region.

Siem Reap has colonial and Chinese-style architecture in the Old French Quarter, and around the Old Market. In the city, there are museums, traditional Apsara dance performances, a Cambodian cultural village, souvenir and handycraft shops, silk farms, rice-paddies in the countryside, fishing villages and a bird sanctuary near the Tonle Sap Lake.

Siem Reap today—being a popular tourist destination—has a large number of hotels, resorts, restaurants and businesses closely related to tourism. This is much owed to its proximity to the Angkor temples, the most popular tourist attraction in Cambodia.

History

The name "Siem Reap" can be translated to mean "Defeat of Siam" (siem in Khmer), and is commonly taken as a reference to an incident in the centuries-old conflict between the Siamese and Khmer kingdoms, although this is probably apocryphal. According to oral tradition, King Ang Chan (1516–1566) had named the town "Siem Reap", meaning "the defeat of Siam", after he repulsed an army sent to invade Cambodia by the Thai King Maha Chakkraphat in 1549. However, scholars consider this derivation to be simply a modern folk etymology, and maintain that the actual origin of the name is unknown.