Name: spectrophotometric methods for the study of eukaryotic glycogen metabolism
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Description: Watch this Scientific Journal Video about Spectrophotometric Methods for the Study of Eukaryotic Glycogen Metabolism at JoVE.com

作者要感谢Karoline Dittmer和Andrew Brittingham的见解和许多有益的讨论。这项工作得到了爱荷华州整骨教育和研究基金（IOER 03-17-05和03-20-04）的部分资助。

1.糖原合酶活性的测定
<ol><li>如 表1 所示制备所需试剂的储备溶液（实验日之前）。</li>
</ol><table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td>元件</td>
			<td colspan="2">方向</td>
		</tr><tr><td>50 毫米三分尺 pH 8.0</td>
			<td colspan="2">将 0.61 g Tris 碱溶解在 ~ 80 mL 水中。 冷却至4°C。  用HCl将pH调节至8.0，用水使体积达到100 mL。</td>
		</tr><tr>...

<ol>
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E., Bowling, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+automated+assay+of+glycogen+phosphorylase+in+the+direction+of+phosphorolysis.">An automated assay of glycogen phosphorylase in the direction of phosphorolysis.</a> Annals of Clinical Biochemistry. 27, 129-132 (1990).</li><li>Nelson, T. E., Kolb, E., Larner, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+and+properties+of+rabbit+muscle+amylo-1,6-glucosidase-oligo-1,4-1,4-transferase.">Purification and properties of rabbit muscle amylo-1,6-glucosidase-oligo-1,4-1,4-transferase.</a> Biochemistry. 8 (4), 1419-1428 (1969).</li><li>Taylor, C., Cox, A. J., Kernohan, J. C., Cohen, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Debranching+enzyme+from+rabbit+skeletal+muscle.+Purification,+properties+and+physiological+role.">Debranching enzyme from rabbit skeletal muscle. Purification, properties and physiological role.</a> European Journal of Biochemistry. 51 (1), 105-115 (1975).</li><li>Makino, Y., Omichi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+glycogen+debranching+enzyme+from+porcine+brain:+evidence+for+glycogen+catabolism+in+the+brain.">Purification of glycogen debranching enzyme from porcine brain: evidence for glycogen catabolism in the brain.</a> Bioscience, Biotechnology, and Biochemistry. 70 (4), 907-915 (2006).</li><li>Lee, E. Y. C., Whelan, W. J., Boyer, P. 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Purification and properties of the Escherichia coli b alpha-1,4,-glucan: alpha-1,4-glucan 6-glycosyltansferase.</a> Biochemistry. 16 (16), 3693-3699 (1977).</li><li>Krisman, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+the+colorimetric+estimation+of+glycogen+with+iodine.">A method for the colorimetric estimation of glycogen with iodine.</a> Analytical Biochemistry. 4, 17-23 (1962).</li><li>Friedman, D. L., Larner, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+UDPG-alpha-glucan+transglucosylase.+iii.+Interconversion+of+two+forms+of+muscle+UDPG-alpha-glucan+transglucosylase+by+a+phosphorylation-dephosphorylation+reaction+sequence.">Studies on UDPG-alpha-glucan transglucosylase. iii. 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一般来说，所介绍的所有方法的主要优点是成本低、简单、速度快，并且不依赖专用设备。与其他可用方法相比，它们共有的主要缺点是灵敏度。涉及生产或消费NADH/NADPH的程序的敏感性很容易估计。鉴于NADH / NADPH的消光系数为6.22 M-1 cm-1，简单的算术表明可以很容易地检测到~10-20μM浓度的变化。使用本文中描述的测定体积，这对应于测量~10-20 nmol范围内的数量的能力。可以说，这?...

糖原在自然界中分布广泛，该化合物存在于细菌、许多原生生物、真菌和动物中。在微生物中，当营养物质有限时，糖原对细胞存活很重要，而在哺乳动物等高等生物中，糖原的合成和降解有助于缓冲血糖水平1，2，3。因此，糖原代谢的研究对微生物学和哺乳动物生理学等不同领域具有重要意义。了解糖原代谢需要研究糖原合成（糖原合酶和支化酶）和糖原降解（糖原磷酸化酶和脱支酶）的关键酶。糖原合酶、磷酸化酶、支化和脱支酶活性的金标准测定采用放射性同位素。例如，糖原合酶通常在停止的放射化学测定中通过将UDP-[14 C]葡萄糖（在动物和真菌酶的情况下）或ADP-[14C]葡萄糖（在细菌酶的情况下）掺入糖原4，5来测量。类似地，在将[14C]葡萄糖-1-磷酸中的葡萄糖掺入糖原6之后，沿糖原合成方向测量糖原磷酸化酶。通过测量该酶通过糖原磷酸化酶7刺激葡萄糖-1-磷酸中的[14C]葡萄糖掺入α1，4-连接链的能力来测定支化酶，并通过跟踪酶将[14C]葡萄糖掺入糖原的能力来确定脱支酶活性8.虽然放射性底物非常敏感，允许它们用于酶活性水平低的粗细胞提取物，但价格昂贵，并且受放射性同位素使用相关的监管要求的约束。这些障碍使许多工人无法使用某些检测方法。然而，在多年的过程中，已经描述了用于测量这些酶的各种令人印象深刻的分光光度法。一般来说，这些方法最终依赖于测量NADH / NADPH的产生或消耗，或糖原和碘之间有色复合物的产生。因此，它们很简单，可以使用仅配备钨或氙闪光灯的简单分光光度计进行。
糖原合酶的分光光度测定依赖于测量糖核苷酸供体释放的核苷二磷酸，因为葡萄糖被添加到生长的糖原链中9，10。下面协议第1节中描述的测量糖原合酶活性的程序是对Wayllace等人11概述的程序的修改，偶联方案如下所示：
（葡萄糖）n + UPD-葡萄糖→ （葡萄糖）n+1 + UDP
UDP + ATP → ADP + UTP
ADP + 磷酸烯醇丙酮酸 → 丙酮酸 + ATP
丙酮酸 + NADH + H+ →乳酸 + NAD+
糖原合酶将UDP-葡萄糖中的葡萄糖添加到糖原上。在此过程中产生的UDP通过核苷二磷酸激酶（NDP激酶）转化为UTP，在产生ADP的反应中。反过来，ADP作为丙酮酸激酶的底物，丙酮酸激酶使用磷酸烯醇丙酮酸作为磷酸供体磷酸化ADP。所得丙酮酸通过乳酸脱氢酶在消耗NADH的反应中转化为乳酸。因此，该测定可以以连续的方式进行，监测消耗NADH时340nm处吸光度的降低。它很容易与需要ADP-葡萄糖作为葡萄糖供体的酶一起使用。在这里，偶联步骤更简单，因为糖原合酶作用释放的ADP直接作用于丙酮酸激酶。
有多种分光光度法可用于测定糖原磷酸化酶活性。在经典版本中，酶向后驱动，朝糖原合成的方向，如下所示：
（葡萄糖）n + 葡萄糖-1-磷酸 → （葡萄糖）n+1 + Pi
在定时间隔下，除去反应混合物的等分试样，并定量释放的磷酸盐量12，13。在我们手中，由于在许多商业制备的葡萄糖-1-磷酸中存在易于测量的游离磷酸盐，以及磷酸化酶作用所需的高浓度葡萄糖-1-磷酸盐，因此该测定的使用有限。相反，我们常规采用另一种测定法，测量糖原被磷酸化酶13降解时释放的葡萄糖-1-磷酸盐。采用下图所示的偶联反应方案。
（葡萄糖）n + Pi → （葡萄糖）n-1 + 葡萄糖-1-磷酸
葡萄糖-1-磷酸 → 葡萄糖-6-磷酸
葡萄糖-6-磷酸 + NADP+ → 6-磷酸葡萄糖酸内酯 + NADPH + H+
葡萄糖-1-磷酸通过磷酸葡萄糖变位酶转化为葡萄糖-6-磷酸，然后将葡萄糖-6-磷酸氧化成6-磷酸葡萄糖酸内酯，同时NADP+ 还原为NADPH。下面协议第2节中详述的程序源自Mendicino等人14 和Schreiber&Bowling15描述的方法。该测定可以很容易地以连续的方式进行，随着时间的推移，340nm处的吸光度增加，从而可以测定反应速率。
分光光度法测定脱支酶活性依赖于测量酶对磷酸化酶极限糊精16的作用释放的葡萄糖。该化合物是通过用糖原磷酸化酶彻底处理糖原制成的。由于糖原磷酸化酶的作用使4个葡萄糖残基远离α1，6支链点，因此极限糊精含有糖原，其外链已缩短至~4个葡萄糖残基。这里描述了磷酸化酶极限糊精的制备，使用源自Taylor等人17 和Makino & Omichi18开发的那些程序。
去分支是一个两步过程。双功能脱支酶的4-α-葡聚糖转移酶活性首先将三个葡萄糖残基从支点转移到附近α1，4-连接的葡萄糖链的非还原端。然后，残留在分支点的单个α1，6-连接葡萄糖残基被α1，6-葡萄糖苷酶活性19水解。该测定通常以停止的方式进行，在给定时间（或一系列时间）后释放的葡萄糖在偶联酶测定中测量如下：
（葡萄糖）n → （葡萄糖）n-1 + 葡萄糖
葡萄糖 + ATP → 葡萄糖-6-磷酸 + ADP
葡萄糖-6-磷酸 + NADP+ → 6-磷酸葡萄糖酸内酯 + NADPH + H+
测定产生的NADPH可以测量葡萄糖的产生量度。下文议定书第3节概述的程序以Nelson等人描述的程序为基础，16。与依赖于NADH / NADPH的消耗或生成的其他方法一样，该测定非常敏感。然而，淀粉酶或其他葡萄糖苷酶的存在（它们也可以从磷酸化酶限制糊精中释放游离葡萄糖）将引起显着干扰（见讨论）。
支化酶活性的比色测定依赖于α1，4-连接的葡萄糖链采用与碘结合的螺旋结构，形成有色复合物的事实20。形成的配合物的颜色取决于α1，4-连接链的长度。因此，直链淀粉由长而大部分未支链的α1，4-连接的葡萄糖组成，与碘形成深蓝色复合物。相反，糖原，其外链通常只有6至8个葡萄糖残基长，形成橙红色复合物。如果直链淀粉溶液与支化酶一起孵育，将支链引入直链淀粉会导致产生较短的α1，4-连接的葡萄糖链。因此，直链淀粉/碘复合物的最大吸收向较短的波长移动。这里讨论的程序源自Boyer&Preiss21 的详细程序，支化酶活性被量化为随着时间的推移在660nm处直链淀粉/碘复合物的吸收减少。
从上面的讨论中应该很容易看出，碘链和α1，4-葡萄糖链之间形成的复合物的颜色随链长而变化的事实意味着糖原/碘复合物的吸光度光谱应随糖原支化程度而变化。情况确实如此，具有较长外链的支链较少的糖原/糖原比支链更细/外链较短的糖原吸收波长更长的光。因此，碘染色反应可用于获得关于糖原支化程度的快速定性数据22。当糖原与碘的复合物不是特别强烈时，形成橙棕色。然而，通过加入饱和氯化钙溶液22可以增强颜色显影。这使该方法的灵敏度提高了约10倍，并允许随时分析微量糖原。下面协议第4节中描述的用于确定分支的测定法改编自Krisman22开发的程序。只需将糖原样品与比色皿中的碘溶液和氯化钙混合并收集330nm至800nm的吸收光谱即可进行。随着分支程度的降低，吸光度最大值向更长的波长移动。
总的来说，这里描述的方法提供了简单，可靠的方法来评估糖原代谢关键酶的活性，并获得有关糖原分支程度的定性数据。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Amylopectin (amylose free) from waxy corn</td>
			<td>Fisher Scientific</td>
			<td>A0456</td>
			<td></td>
		</tr>
		<tr>
			<td>Amylose</td>
			<td>Biosynth Carbosynth</td>
			<td>YA10257</td>
			<td></td>
		</tr>
		<tr>
			<td>ATP, disodium salt</td>
			<td>MilliporeSigma</td>
			<td>A3377</td>
			<td></td>
		</tr>
		<tr>
			<td>D-Glucose-1,6-bisphosphate, potassium salt</td>
			<td>MilliporeSigma</td>
			<td>G6893</td>
			<td></td>
		</tr>
		<tr>
			<td>D-glucose-6-phosphate, sodium salt</td>
			<td>MilliporeSigma</td>
			<td>G7879</td>
			<td></td>
		</tr>
		<tr>
			<td>Glucose-6-phosphate dehydrogenase, Grade I, from yeast</td>
			<td>MilliporeSigma</td>
			<td>10127655001</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycogen, Type II from oyster</td>
			<td>MilliporeSigma</td>
			<td>G8751</td>
			<td></td>
		</tr>
		<tr>
			<td>Hexokinase</td>
			<td>MilliporeSigma</td>
			<td>11426362001</td>
			<td></td>
		</tr>
		<tr>
			<td>Methacrylate cuvettes, 1.5 mL</td>
			<td>Fisher Scientific</td>
			<td>14-955-128</td>
			<td>Methacrylate is required since some procedures are conducted at 340 nm or below</td>
		</tr>
		<tr>
			<td>&#946;-Nicotinamide adenine dinucleotide phosphate sodium salt</td>
			<td>MilliporeSigma</td>
			<td>N0505</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;-Nicotinamide adenine dinucleotide, reduced disodium salt</td>
			<td>MilliporeSigma</td>
			<td>43420</td>
			<td></td>
		</tr>
		<tr>
			<td>Nucleoside 5&#39;-diphosphate kinase</td>
			<td>MilliporeSigma</td>
			<td>N0379</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphoenolpyruvate, monopotassium salt</td>
			<td>MilliporeSigma</td>
			<td>P7127</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphoglucomutase from rabbit muscle</td>
			<td>MilliporeSigma</td>
			<td>P3397</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphorylase A from rabbit muscle</td>
			<td>MilliporeSigma</td>
			<td>P1261</td>
			<td></td>
		</tr>
		<tr>
			<td>Pyruvate Kinase/Lactic Dehydrogenase enzymes from rabbit muscle</td>
			<td>MilliporeSigma</td>
			<td>P0294</td>
			<td></td>
		</tr>
		<tr>
			<td>UDP-glucose, disodium salt</td>
			<td>MilliporeSigma</td>
			<td>U4625</td>
			<td></td>
		</tr>
	</tbody>
</table>

spectrophotometric methods for the study of eukaryotic glycogen metabolism

糖原是由从细菌到动物的各种生物体合成的葡萄糖储存形式。该分子包括α1，4-连接的葡萄糖残基的线性链，其分支通过添加α1，6-连接引入。了解糖原的合成和降解如何被调节以及糖原如何获得其特征性的支链结构需要研究糖原储存的酶。然而，最常用于研究这些酶活性的方法通常采用并非所有研究人员都可以使用的试剂或技术。在这里，我们讨论了一系列技术上简单，具有成本效益的程序，但仍能够为糖原储存的控制提供有价值的见解。这些技术需要使用在330至800nm范围内的分光光度计，并且假设用户将使用一次性塑料比色皿进行描述。然而，该程序易于扩展，并且可以修改以用于酶标仪，从而实现高度平行的分析。

糖原合酶活性的测定 图1 显示了使用纯化酶进行糖原合酶测定的代表性结果。在图A中，在轻微滞后之后，随着时间的推移，340nm处的吸收呈线性下降，持续约12分钟。 图1A 中的吸收变化率为~0.12吸光度单位/分钟。~0.010至~0.20吸光度单位/min之间的吸光度变化率是最佳的，应将糖原合酶的添加量调整为该范围内的产量。在图B中，显示了在测?...

Watch this Scientific Journal Video about Spectrophotometric Methods for the Study of Eukaryotic Glycogen Metabolism at JoVE.com

Spectrophotometric Methods for the Study of Eukaryotic Glycogen Metabolism

介绍了使用在可见光范围内操作的简单分光光度计测量糖原代谢关键酶活性的技术。

用于研究真核糖原代谢的分光光度法

Glycogen is synthesized as a storage form of glucose by a wide array of organisms, ranging from bacteria to animals. The molecule comprises linear chains ...

这些协议意义重大，因为它们避免使用放射性同位素，并消除了可能阻止许多工人研究糖原代谢酶的屏障。所描述的程序价格低廉，只需要使用简单的分光光度计。首先测定糖原合酶活性，在冰上解冻先前制备的UDP葡萄糖，ATP，磷酸烯醇丙酮酸和NDP激酶储备溶液。将水浴预热至30摄氏度。当储备溶液准备好时，通过将试剂添加到15毫升管中，根据糖原合酶测定的数量准备足够的测定混合物，如文本协议中所述。通过用水代替反应混合物中的NADH来制备空白反应，并将反应转移到一次性甲基丙烯酸比色皿中。使用空白反应在分光光度计上将零设置为340纳米波长。在1.5毫升管中取一个770微升等分试样的反应混合物，并依次向管中加入NDP激酶和丙酮酸激酶乳酸脱氢酶混合物各两微升。混合后，将管在水浴中以30摄氏度轻轻孵育三分钟，以预热反应混合物。然后在pH 7.8的20毫摩尔Tris缓冲液中加入30微升含有糖原合酶的样品，并在将反应混合物转移到处置的甲基丙烯酸比色皿之前轻轻混合。将比色皿放入分光光度计中，并以定时间隔记录340纳米处的吸光度10至20分钟。然后，绘制获得的吸光度与时间的关系图。为了测量释放的葡萄糖，将40微升上清液从加热的糖原样品转移到一次性甲基丙烯酸酯比色皿中。并加入手稿中描述的三乙醇胺、盐酸硫酸镁缓冲液、NADP ATP混合物和水的测定体积。通过轻轻上下移液混合混合物，不要产生气泡。向每个比色皿中加入0.5微升葡萄糖-6-磷酸脱氢酶。通过移液混合后，将混合物在室温下孵育10分钟，然后在340纳米处记录吸光度。接下来，如前所述将0.5微升己糖激酶混合到每个比色皿中，并在记录吸收剂组340纳米之前孵育15分钟。然后继续在室温下孵育五分钟，然后记录吸光度。如果吸收比15分钟记录的吸收增加，则继续孵育5分钟，然后记录340纳米处的最终吸收。为了确定糖原支链，将650微升碘氯化钙彩色试剂原液与100微升水混合在1.5毫升管中，并在转移到一次性甲基丙烯酸比色皿之前彻底混合溶液。将比色皿放入分光光度计中，以波长扫描模式进行运行，以收集330至800纳米的背景光谱。在一个单独的1.5毫升管中，将650微升的工作碘氯化钙颜色试剂与50微克牡蛎糖原混合，并用水将最终体积补足至750微升。彻底混合混合物后，将溶液转移到一次性甲基丙烯酸酯比色皿中，以收集330至800纳米的吸收光谱。同样，如前所述，获得含有50微克支链淀粉和30微克直链淀粉的吸收光谱。为了获得未表征糖原样品的支链结构的指示，将25至50微克糖原与650微升工作碘氯化钙颜色试剂混合，并按照前面的说明进行以获得吸收光谱。在糖原合酶测定中，观察到340纳米处的吸收随时间线性降低。在测定中添加过多的糖原合酶导致反应在前两分钟内完成。对照反应不含糖原合酶，没有显示可测量的吸光度降低。使用纯化酶的糖原磷酸化酶测定的数据具有持续三分钟的线性相。吸光度增加速率约为每分钟 0.01 至 0.04 单位是最佳的。在糖原脱支酶测定中，反应显示线性相持续至少10分钟。来自糖原支化酶测定的代表性数据显示，缺乏支化酶的对照样品与含有支化酶的反应之间的吸光度存在差异。图中说明了测定的窄动态范围。可以产生的吸光度的最大变化为0.4个吸光度单位，当吸收的变化约为0.2个吸光度单位时，线性就会丢失。糖原支链评估中使用的糖原、支链淀粉和直链淀粉的质量数显示出约0.7至0.8的最大吸光度读数，每个读数在不同的最大吸光度下。糖原样品在大约400纳米和460纳米处产生两个峰。碘氯化钙颜色试剂非常致密。在收集吸收光谱之前，确保糖原样品与试剂完全混合非常重要。

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A Method for Measuring Metabolism in Sorted Subpopulations of Complex Cell Communities Using Stable Isotope Tracing

一种用于在复杂的细胞群落稳定性同位素示踪排序亚群测量方法代谢

Mammalian cell types exhibit specialized metabolism, and there is ample evidence that various co-existing cell types engage in metabolic cooperation. ...

科研

生物化学

Tandem Affinity Purification of Protein Complexes from Eukaryotic Cells

从真核细胞蛋白质复合体串联亲和纯化

The purification of active protein-protein and protein-nucleic acid complexes is crucial for the characterization of enzymatic activities and de novo ...

Determination of the Glycogen Content in Cyanobacteria

测定蓝细菌中的糖原含量

Cyanobacteria accumulate glycogen as a major intracellular carbon and energy storage&#160;during photosynthesis. Recent developments in research have ...

Small-Scale Colorimetric Assays of Intracellular Lactate and Pyruvate in the Nematode Caenorhabditis elegans

Small-Scale Colorimetric Assays of Intracellular Lactate and Pyruvate in the Nematode Caenorhabditis elegans

线虫线虫中乳酸和丙酮酸细胞的小尺度比色测定

Lactate and pyruvate are key intermediates of intracellular energy metabolic pathways. Monitoring the lactate/pyruvate ratio in cells helps to determine ...

Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis

Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis

分光光度法测定蓝藻Synechocystis中的蛋白含量

This is a simple protocol for the quantitative determination of phycobiliprotein content in the model cyanobacterium Synechocystis. Phycobiliproteins are ...

Single Liposome Measurements for the Study of Proton-Pumping Membrane Enzymes Using Electrochemistry and Fluorescent Microscopy

电化学和荧光显微镜在质子泵膜酶研究中的单脂质体测定

Proton-pumping enzymes of electron transfer chains couple redox reactions to proton translocation across the membrane, creating a proton-motive force used ...

Expression, Solubilization, and Purification of Eukaryotic Borate Transporters

真核硼酸背液转运体的表达、增溶及纯化

The Solute Carrier 4 (SLC4) family of proteins is called the bicarbonate transporters and includes the archetypal protein Anion Exchanger 1 (AE1, also ...

Study on the Metabolism of Six Systemic Insecticides in a Newly Established Cell Suspension Culture Derived from Tea (Camellia Sinensis L.) Leaves

Study on the Metabolism of Six Systemic Insecticides in a Newly Established Cell Suspension Culture Derived from Tea Camellia Sinensis L. Leaves

从茶中提取的新建细胞悬浮培养基中六种系统杀虫剂的代谢研究(山茶西宁西斯L.叶

A platform for studying insecticide metabolism using in vitro tissues of tea plant was developed. Leaves from sterile tea plantlets were induced to form ...

SUMO-Binding Entities (SUBEs) as Tools for the Enrichment, Isolation, Identification, and Characterization of the SUMO Proteome in Liver Cancer

SUMO-Binding Entities SUBEs as Tools for the Enrichment, Isolation, Identification, and Characterization of the SUMO Proteome in Liver Cancer

SUMO 结合实体 （SUBEs） 作为肝癌中 SUMO 蛋白酶的浓缩、分离、识别和表征的工具

Post-translational modification is a key mechanism regulating protein homeostasis and function in eukaryotic cells. Among all ubiquitin-like proteins in ...

An Integrated Raman Spectroscopy and Mass Spectrometry Platform to Study Single-Cell Drug Uptake, Metabolism, and Effects

一个集成拉曼光谱和质谱平台，用于研究单细胞药物接受、代谢和效果

Cells are known to be inherently heterogeneous in their responses to drugs. Therefore, it is essential that single-cell heterogeneity is accounted for in ...