Overview:
FLT3 is a receptor tyrosine kinase that has been shown to play a role in proliferation and survival of hematopoietic progenitor cells as well as differentiation of early B lymphoid progenitors (1). FLT3 consists of an extracellular domain composed of five immunoglobulin-like domains, one transmembrane region, and a cytoplasmic kinase domain split into two parts by a kinase-insert domain. FLT3 is the most frequently mutated gene in cases of acute myelogenous leukemia (AML). About 30% to 35% of patients have either internal tandem duplications (ITDs) in the juxtamembrane domain or mutations in the activating loop of FLT3 (2). The consequence of either FLT3-ITD or activating loop mutations is the constitutive activation of the tyrosine kinase activity.
Gene Aliases:
FLK2, STK1, CD135
Genbank Number:
NM_004119
References:
1. Christensen, J L. et al : Flk-2 is a marker in hematopoietic stem cell differentiation: a simple method to isolate long-term stem cells. Proc. Nat. Acad. Sci. 98: 14541-14546, 2001.2. Gilliland, D G. et al: Role of FLT3 in leukemia. Curr Opin Hematol. 2002 Jul;9(4):274-81.
ebiomall.com
>
>
>
>
>
>
>
>
>
>
>
>
1、测定酶比活力:底物需要过量么?测定时间多长?是否可以加入过量的底物,然后测定3min吸光度的增加值,从吸光度的变化值计算比活力。
2、在酶抑制剂筛选的过程中,是否需要保证底物过量?还是要水浴一定时间让反应完全?我看到文献说用终浓度为0.1μmol/mL的底物,终浓度为45U/ml的酶,我想问,假设总体积为1ml,那么终浓度为45U/ml的酶岂不是每分钟能转化4.8μmol的底物?那么0.1μmol/mL的底物不就几秒钟就反应完了?那么怎么测定初速度?
《血管紧张素转换酶抑制剂在心血管病中应用的中国专家共识》.PDF(242.69k)
1.对于抑制剂筛选工作(求ic50)是不是体系内酶与底物的量(底物应该是过量的)对实验结果影响不大。
2.如果要求算Km值,是不是需要知道反应产物的绝对量。反应时间文献上都是5分钟,反应速度就用反应产物量除以反应时间即可。
3.酶是进口分装的,规格5U,一次用不完,用PBS稀释后如何保存
谢谢
2、可逆抑制剂:包括
a、竞争性抑制剂,抑制剂与底物竞争性结合酶反应中心,使Km增大,而Vmax不变 b、非竞争性抑制剂,酶与抑制剂结合后还能与底物结合,但活性降低,使Vmax减小,而Km不变
c、反竞争性抑制剂,酶只能与底物结合后才能与抑制剂结合,Vmax与Km都减小
可逆抑制剂可用透析等方法除去,使酶恢复作用
暂无品牌问答