Doctoral Dissertation Research: Dissecting the effect of encephalization on skull morphogenesis

博士论文研究：剖析脑化对头骨形态发生的影响

基本信息

批准号：
1731909
负责人：
Joan Richtsmeier
金额：
$ 3.14万
依托单位：
Pennsylvania State Univ University Park
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-01 至 2019-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1731909&HistoricalAwards=false
关键词：
Doctoral Dissertation Research Dissecting effect

项目摘要

Dramatic increases in cranial capacity have occurred in hominins. These shifts in relative brain size are hypothesized to have caused (1) alterations to the modern human skull and (2) delays or reductions in somatic growth that may affect skull development. While prior studies have used fossil or comparative primate data to understand the relationship between the brain and skull, this project utilizes an experimental approach to link the process of encephalization with specific changes in skull morphology. The results of this project will be incorporated into multiple educational and outreach activities designed to stimulate interest in younger students pursuing STEM fields and careers, particularly young women, and foster awareness of the interdisciplinary potential for biological anthropology. Through the Penn State Expanding Your Horizons STEM Career Day for Women and the ScienceU Pre-Med Expo, the researchers will help students understand the morphological changes that have occurred in the human skull over time, including the specific impact of encephalization.This project uses the BAF170 murine model with a known genetic variant that results in an enlarged brain phenotype. The BAF170 gene is knocked-out only in cortical tissue resulting in an enlarged cortex, such that any changes in the skull can only be attributed to the effect of the larger cortex. Using high-resolution micro-computed tomography data of prenatal and early postnatal skull development, this research will test whether an increase in relative brain size affects somatic growth of the skull or causes changes in cranial development or eventual morphology. Experiments are designed to determine whether the change in brain size causes changes in: (1) the timing of the appearance/formation of cranial ossification centers during embryological development; (2) cranial bone quality, evaluated by quantifying bone volume and bone density; or (3) morphology of the cranial base, cranial vault, or facial skeleton that can be compared with similar changes seen through time in hominins. These experiments will test the spatial packing hypothesis and the expensive brain hypothesis, by examining the relationship between brain size and cranial base angle and between changes in brain size and somatic ontogenetic trajectories. The resulting data will provide experimental evidence pertaining to the relationship between encephalization in hominins and changes in skull morphology and growth producing the unique human skull phenotype.

人类蛋白中发生了颅骨能力的急剧增加。假设这些相对脑大小的转变已引起（1）对现代人类头骨的改变，以及（2）可能影响颅骨发育的躯体生长的延迟或减少。虽然先前的研究使用化石或比较灵长类动物数据来了解大脑与头骨之间的关系，但该项目采用了一种实验方法将脑化的过程与颅骨形态的特定变化联系起来。该项目的结果将纳入多种教育和外展活动中，旨在激发人们对追求STEM领域和职业（尤其是年轻女性）的年轻学生的兴趣，并提高人们对生物人类学的跨学科潜力的认识。通过宾夕法尼亚州扩大您的地平线的妇女和科学预科博览会，研究人员将帮助学生了解人类颅骨随着时间的流逝所发生的形态学变化，包括脑化的特定影响。本项目使用BAF170 Murine Model使用一种已知的遗传变体，在扩大的脑脑势型中产生的已知遗传变体。 BAF170基因仅在皮质组织中被淘汰，从而导致皮质增大，因此头骨的任何变化只能归因于较大的皮质的效果。该研究使用产前和早期颅骨发育的高分辨率微型层析成像数据，该研究将测试相对脑大小的增加是否会影响颅骨的体细胞生长或导致颅骨发育的变化或最终形态。实验旨在确定脑大小的变化是否导致：（1）胚胎发育过程中颅骨化中心外观/形成的时机；（2）颅骨质量，通过量化骨骼体积和骨密度评估；或（3）可以将颅底，颅库或面部骨骼的形态与人类蛋白的相似变化进行比较。这些实验将通过检查脑大小与颅底角度之间的关系以及大脑大小与体细胞遗传学轨迹之间的关系来检验空间堆积假设和昂贵的大脑假设。最终的数据将提供与人类脑脑化与颅骨形态变化和生长产生独特人颅骨表型之间关系的实验证据。