Together, our findings raise the intriguing possibility that integration of neural crest into the endostyle developmental program may reflect an important evolutionary step in thyroid development and particularly in the formation of a bilobed gland.

Interestingly, our results align with findings in chick embryos, where neural crest ablation leads to hypoplasia or aplasia of pharyngeal-derived endocrine glands (e.g. thyroid gland-Maeda et al., 2016).

We then asked: What happens when neural crest development is disrupted? Using CRISPR/Cas9 to mutate several genes from the neural crest gene regulatory network, we generated crispants with single-lobed endostyles that morphologically resemble those of non-vertebrate chordates.

Since the neural crest — a cell type unique to vertebrates — plays a key role in thyroid development, we asked: does it also help build the lamprey endostyle? Our lineage tracing revealed that it does, contributing even to cells destined to become the thyroid.

While non-vertebrate chordates have simple, groove-like endostyles, lampreys boast a bilobed version packed with specialized cells — including the precursors of adult thyroid follicles.

In this #evodevo project, we explored how the #neuralcrest influences the development of the endostyle — the evolutionary precursor of the thyroid gland. The endostyle, an endoderm-derived organ unique to chordates and key to filter feeding, is found in vertebrates only in #lamprey

Interestingly, our results align with findings in chick embryos, where neural crest ablation leads to hypoplasia or aplasia of pharyngeal-derived endocrine glands (e.g. thyroid gland - Maeda et al.,2016)

We then asked: What happens when neural crest development is disrupted? Using CRISPR/Cas9 to mutate several genes from the neural crest gene regulatory network, we generated crispants with single-lobed endostyles that morphologically resemble those of non-vertebrate chordates.

Since the neural crest— a cell type unique to vertebrates — plays a key role in thyroid development, we asked: does it also help build the lamprey endostyle? Our lineage tracing revealed that it does, contributing even to cells destined to become the thyroid.

While non-vertebrate chordates have simple, groove-like endostyles, lampreys boast a bilobed version packed with specialized cells — including the precursors of adult thyroid follicles.

In this project, we explored how the #neuralcrest influences the development of the endostyle — the evolutionary precursor of the thyroid gland. The endostyle, an endoderm-derived organ unique to chordates and key to filter feeding, is found in vertebrates only in #lamprey

Totally unexpected — but incredibly exciting🎉 My K99/R00 application has been awarded! I can’t wait to dive deeper into exploring the “ancient” developmental program of the neural crest in dermal bone formation.

Beautiful piece! Here is a Czech variant from South California 🫡 Happy New Year 🎈