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Title: The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: CO Excitation and Atomic Carbon in Star-forming Galaxies at z = 1–3
Award ID(s):
1910107
NSF-PAR ID:
10330867
Author(s) / Creator(s):
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Date Published:
Journal Name:
The Astrophysical Journal
Volume:
902
Issue:
2
ISSN:
1538-4357
Page Range / eLocation ID:
109
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Vertebrate eye formation requires coordinated inductive interactions between different embryonic tissue layers, first described in amphibians. A network of transcription factors and signaling molecules controls these steps, with mutations causing severe ocular, neuronal, and craniofacial defects. Ineyelessmutant axolotls, eye morphogenesis arrests at the optic vesicle stage, before lens induction, and development of ventral forebrain structures is disrupted.

    Results

    We identified a 5‐bp deletion in therax(retina and anterior neural fold homeobox) gene, which was tightly linked to the recessiveeyeless(e) axolotl locus in an F2 cross. This frameshift mutation, in exon 2, truncates RAX protein within the homeodomain (P154fs35X). Quantitative RNA analysis shows that mutant and wild‐typeraxtranscripts are equally abundant inE/eembryos. Translation appears to initiate from dual start codons, via leaky ribosome scanning, a conserved feature among gnathostome RAX proteins. Previous data showraxis expressed in the optic vesicle and diencephalon, deeply conserved among metazoans, and required for eye formation in other species.

    Conclusion

    Theeyelessaxolotl mutation is a null allele in theraxhomeobox gene, with primary defects in neural ectoderm, including the retinal and hypothalamic primordia.

     
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  3. null (Ed.)