Disease relevance of TAC4

• Moreover, we show TAC4 mRNA expression in gliomas, indicating a possible involvement of HK-1 in glioma biology [1].
• In this study, we compared the effects of SP with those of the novel tachykinin Hemokinin-1 (HK-1) in the human astrocytoma cell line U-251 MG [1].
• Establishment of a cell line (NPC/HK1) from a differentiated squamous carcinoma of the nasopharynx [2].

High impact information on TAC4

• However, HK-1 also has properties that are indicative of a critical role in mouse B cell development [3].
• Loss of one copy of chromosome 10 which carries the HK1 gene, was evidenced in 11 of the 13 xenografted gliomas [4].
• These data 1) show for the first time that hHK-1 is a uterine stimulant in the human, 2) confirm that the NK2 receptor is predominant in mediating tachykinin actions on the human myometrium, and 3) indicate that mammalian tachykinin effects are tightly regulated during pregnancy in a manner that would negate an inappropriate uterotonic effect [5].
• The effects of neurokinin A (NKA) and human hemokinin-1 (hHK-1) in tissues from pregnant but not from nonpregnant women were enhanced by the inhibition of neprilysin [5].
• Human HK-1 acted as a partial agonist blocked by SR 48968 and, to a lesser extent, by SR 140333; endokinin D was inactive [5].

Anatomical context of TAC4

• Recent studies suggest HK-1 may have a role in immunological functions, but there has been little characterization of HK-1's effects in the central nervous system (CNS) [6].
• CHO cells transfected with the human NK1 receptor released intracellular calcium in response to HK-1 [6].

Associations of TAC4 with chemical compounds

• Furthermore, the TAC4 encoded tachykinins all exhibit a remarkable selectivity and potency for the highly species conserved tachykinin NK(1) receptor, similar to that of substance P [7].
• In vivo central administration of HK-1 to gerbils and mice induced foot-tapping and scratching behaviors, respectively, similar to those observed following central administration of SP or the NK1 receptor agonist, GR-73632 [6].

Analytical, diagnostic and therapeutic context of TAC4

• We report here the molecular cloning of a newly identified preprotachykinin gene, Pptc, which specifies the sequence for a new preprotachykinin protein and bioactive peptide designated hemokinin 1 (HK-1) [3].
• RAST inhibition and ELISA showed that modified PPT C. arizonica extract had less IgE reactivity than the native, non-modified extract, while preserving the immunogenic capacity typical for an allergoid [8].
• RESULTS: Direct RAST, RAST inhibition, and SDS-PAGE data indicated that the PPT C. arizonica pollen extract showed the most allergenic potential, and it can be considered representative of the Cupressus spp [8].
• To assess the effect of a mutated K1 gene on skin biology and to produce an animal model for EHK, we removed 60 residues from the 2B segment of HK1 and observed the effects of its expression in the epidermis of transgenic mice [9].

References