Liver X receptor beta (LXR-β) is a member of the nuclear receptor family of transcription factors. LXR-β is encoded by the NR1H2 gene (nuclear receptor subfamily 1, group H, member 2).[5]
The liver X receptors (LXRs) were originally identified as orphan members of the nuclear receptor superfamily because their ligands were unknown. Like other receptors in the family, LXRs heterodimerize with retinoid X receptor and bind to specific response elements (LXREs) characterized by direct repeats separated by 4 nucleotides. Two genes, alpha (LXRA) and beta, are known to encode LXR proteins.[5][6]
Crystal structure of human liver X receptor β(LXRβ) forming heterodimer with its partner retinoid X receptor α(RXRα) on its cognate element, an AGGTCA direct repeat spaced by 4 nt shows an extended X-shaped arrangement, with DNA- and ligand-binding domains crossed. The LXRβ core binds DNA via canonical contacts and auxiliary DNA contacts that enhance affinity for the response element.[7]
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^Lou X, Toresson G, Benod C, Suh JH, Philips KJ, Webb P, Gustafsson JA (Mar 2014). "Structure of the retinoid X receptor α-liver X receptor β (RXRα-LXRβ) heterodimer on DNA". Nature Structural & Molecular Biology. 21 (3): 277–81. doi:10.1038/nsmb.2778. PMID24561505. S2CID23226682.
Le Beau MM, Song C, Davis EM, Hiipakka RA, Kokontis JM, Liao S (Mar 1995). "Assignment of the human ubiquitous receptor gene (UNR) to 19q13.3 using fluorescence in situ hybridization". Genomics. 26 (1): 166–8. doi:10.1016/0888-7543(95)80100-Z. PMID7782080.
Shinar DM, Endo N, Rutledge SJ, Vogel R, Rodan GA, Schmidt A (Sep 1994). "NER, a new member of the gene family encoding the human steroid hormone nuclear receptor". Gene. 147 (2): 273–6. doi:10.1016/0378-1119(94)90080-9. PMID7926814.
Hoerer S, Schmid A, Heckel A, Budzinski RM, Nar H (Dec 2003). "Crystal structure of the human liver X receptor beta ligand-binding domain in complex with a synthetic agonist". Journal of Molecular Biology. 334 (5): 853–61. doi:10.1016/j.jmb.2003.10.033. PMID14643652.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction