Department of Biology, Howard University, Washington, DC.
Department of Oral Pathology, Howard University, Washington, DC.
JCO Clin Cancer Inform. 2024 Jan;8:e2300140. doi: 10.1200/CCI.23.00140.
Thyroid peroxidase (TPO) is essential for the synthesis of thyroid hormones. However, specific mutations render TPO antigenic and prone to autoimmune attacks leading to thyroid cancer, TPO deficiency, and congenital hypothyroidism (CH). Despite technological advancement, most experimental procedures cannot quickly identify the genetic causes of CH nor detect thyroid cancer in the early stages.
We performed saturated computational mutagenesis to calculate the folding energy changes (∆∆G) caused by missense mutations and analyzed the mutations involved in post-translational modifications (PTMs).
Our results showed that the functional important missense mutations occurred in the heme peroxidase domain. Through computational saturation mutagenesis, we identified the TPO mutations in G393 and G348 affecting protein stability and PTMs. Our folding energy calculations revealed that seven of nine somatic thyroid cancer mutations destabilized TPO.
These findings highlight the impact of these specific mutations on TPO stability, linking them to thyroid cancer and other genetic thyroid-related disorders. Our results show that computational mutagenesis of proteins provides a quick insight into rare mutations causing Mendelian disorders and cancers in humans.
甲状腺过氧化物酶(TPO)是合成甲状腺激素所必需的。然而,特定的突变会使 TPO 具有抗原性,并容易受到自身免疫攻击,从而导致甲状腺癌、TPO 缺乏症和先天性甲状腺功能减退症(CH)。尽管技术有所进步,但大多数实验程序仍无法快速确定 CH 的遗传原因,也无法在早期检测到甲状腺癌。
我们进行了饱和计算突变分析,以计算错义突变引起的折叠能变化(∆∆G),并分析了涉及翻译后修饰(PTMs)的突变。
我们的结果表明,功能重要的错义突变发生在血红素过氧化物酶结构域。通过计算饱和突变分析,我们确定了 G393 和 G348 中的 TPO 突变会影响蛋白质稳定性和 PTMs。我们的折叠能计算表明,九种体细胞甲状腺癌突变中有七种会使 TPO 不稳定。
这些发现强调了这些特定突变对 TPO 稳定性的影响,将其与甲状腺癌和其他与遗传相关的甲状腺疾病联系起来。我们的结果表明,蛋白质的计算突变分析为快速了解导致孟德尔疾病和人类癌症的罕见突变提供了线索。