The effects of the excision of Hensen's node on the early development of the chick embryo

Grabowski, Casimer T.

doi:10.1002/jez.1401330207

Cited by 63 publications

(27 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Cultured embryos were categorized as follows: as "good" (normal and/or stunted rostrocaudally or with small neural tube defects; E 35%, C 46%); "fair" (with large neural tube defects; E 28%, C 27%); "inverted" (head inverted into the hole created by surgery; E 24%, C 0%); or "poor" (not shown; failed to develop; E 13%, C 27%). Similar morphology after this type of surgery and culture has been described previously (Grabowski, 1956;Schoenwolf, 1989, 1991).…”

Section: Surgery and Culturesupporting

confidence: 80%

“…2A,B); an additional 26 cultured embryos received no surgery and served as controls. Hensen's node contains the precursor cells of the notochord, and its extirpation can result in the loss of the cranial notochord from developing embryos (Grabowski, 1956). After 24 hours in culture, all 225 embryos were grouped in the following categories based on their gross appearance (Table 1): "good," "fair," "inverted," or "poor" (see Fig.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Changes in dorsoventral but not rostrocaudal regionalization of the chick neural tube in the absence of cranial notochord, as revealed by expression of Engrailed‐2

Darnell

Schoenwolf

Ordahl

1992

Developmental Dynamics

View full text Add to dashboard Cite

Notochord has been implicated in previous studies in both the dorsoventral and rostrocaudal patterning of the developing neural tube. This possibility has been further explored by analyzing the expression of Engruiled-2 in chick embryos developing with cranial notochord defects. Control embryos containing intact notochords expressed Engruiled-2 protein within the neural tube and in a subset of the neural crest and overlying surface ectoderm at the future mesencephalon and cranial metencephalon levels. Within the neural tube, expression was confined to cell nuclei in the roof plate and lateral walls; floor plate nuclei directly overlying the notochord typically failed to show expression. After surgical removal of Hensen's node, the source of notochord precursor cells, embryos were cultured through neurulation and assayed for expression of Engrailed-2 protein. All embryos that partially or completely lacked cranial notochord expressed Engrailed-2 in a pattern similar to that of control embryos containing intact notochords, except that when notochord and floor plate were absent, Engrailed-2 was also expressed in the most ventral part of the neural tube. These results indicate that 1) Engruiled-2 expression is suppressed in the most ventral neural tube owing to induction of the floor plate by the notochord, and 2) that the presence of an underlying notochord is not required for correct rostrocaudal expression, suggesting that multiple pathways act in the patterning of the rudiment of the central nervous system. 0 1992 Wiley-Liss, Inc.

show abstract

Section: Surgery and Culturesupporting

confidence: 80%

Section: Introductionmentioning

confidence: 99%

Changes in dorsoventral but not rostrocaudal regionalization of the chick neural tube in the absence of cranial notochord, as revealed by expression of Engrailed‐2

Darnell

Schoenwolf

Ordahl

1992

Developmental Dynamics

View full text Add to dashboard Cite

show abstract

“…Explants of Hensen's node to the embryonic coelom or germ cell crescent form endoderm, notochord, mesenchyme, and somites (Veini and Hara, 1975;Dias and Schoenwolf, 1990), with the particular structures formed from the explant being dependent on the stage of the node at the time of explantation. As shown in the present study and previous studies (Waddington, 1932;Spratt, 1955;Grabowski, 1956;Gallera and Nicolet, 1974;Schoenwolf, 1989, 1991) extirpation of Hensen's node gives varying results. This variation is apparently owing to the extent of healing of the extirpation site; deficits occur, especially in the notochord and MHP region of the neural tube, if healing is delayed or incomplete (e.g., in Spratt, 1947, culture).…”

Section: Ability Of Primitive Streak Cells To Self-differentiatesupporting

confidence: 59%

Positional control of mesoderm movement and fate during avian gastrulation and neurulation

García‐Martínez

Schoenwolf

1992

Developmental Dynamics

View full text Add to dashboard Cite

Segments of primitive streak from donor quail embryos at stages of gastrulation and neurulation were transplanted heterotopically and isochronically to primitive streaks of host chick embryos. The subsequent movement and fate of grafted cells was determined using the quail nucleolar marker to define grafted cells. The pattern of movement of grafted cells depended on their new position within the primitive streak, not on their original position. When cells of cranial regions were placed more caudally, they moved to mesodermal subdivisions that were located lateral to those they would have populated if left in their original position. When caudal segments were placed more cranially, they moved to more medial mesodermal subdivisions. Whether the fate of grafted cells corresponded to their original location or their new location depended on both their level of origin and their new position. Cells from heterotopically transplanted Hensen's nodes, which migrated to the somitic and more lateral mesoderm, self‐differentiated notochords. Similarly, in some cases, heterotopically transplanted prospective somitic cells, which migrated to lateral plate mesoderm, formed ectopic somites. In other cases, however, grafted cells contributed to the host's somites, intermediate mesoderm, and lateral plate mesoderm. Moreover, prospective somitic cells, which migrated to the extraembryonic lateral plate mesoderm, changed their fate and formed extraembryonic lateral plate mesoderm; and prospective lateral plate mesoderm cells, which migrated to the somitic mesoderm, formed somites as well as intermediate mesoderm and lateral plate mesoderm. These results suggest that the movement of primitive streak cells to various mediolateral subdivisions of the mesodermal stream is determined solely by their craniocaudal position within the streak, but that determination of cell fate involves a combination of self‐differentiation and positional regulation. Cells from cranial levels of the primitive streak exhibit a considerably greater potential to self‐differentiate than those from more caudal levels, and cranial cells are more likely to migrate as a coherent group, unlike more caudal cells, which tend to freely disperse within host structures. © 1992 Wiley‐Liss, Inc.

show abstract

“…When dissected and cultured in a neutral or ectopic environment, pieces of streak tissue taken from along its anteroposterior (A/P) length tend to differentiate into the mesoderm lineages of their respective D/V identities (Abercrombie and Waddington, 1937;Garcia-Martinez and Schoenwolf, 1992;Nakazawa et al, 2006). Yet, experiments in which regions of the streak were extirpated or reversed anteroposteriorly indicated a labile D/V specification among streak cells and a regulative interaction between mesoderm precursors located in the streak and those located in the surrounding epiblast region (Abercrombie, 1950;Abercrombie and Bellairs, 1954;Garcia-Martinez and Schoenwolf, 1992;Grabowski, 1956;Joubin and Stern, 1999;Psychoyos and Stern, 1996b).…”

Section: Introductionmentioning

confidence: 99%

Transcriptomic landscape of the primitive streak

Alev¹,

Wu²,

Kasukawa

et al. 2010

Development

View full text Add to dashboard Cite

SUMMARYIn birds and mammals, all mesoderm cells are generated from the primitive streak. Nascent mesoderm cells contain unique dorsoventral (D/V) identities according to their relative ingression position along the streak. Molecular mechanisms controlling this initial phase of mesoderm diversification are not well understood. Using the chick model, we generated high-quality transcriptomic datasets of different streak regions and analyzed their molecular heterogeneity. Fifteen percent of expressed genes exhibit differential expression levels, as represented by two major groups (dorsal to ventral and ventral to dorsal). A complete set of transcription factors and many novel genes with strong and region-specific expression were uncovered. Core components of BMP, Wnt and FGF pathways showed little regional difference, whereas their positive and negative regulators exhibited both dorsal-to-ventral and ventral-to-dorsal gradients, suggesting that robust D/V positional information is generated by fine-tuned regulation of key signaling pathways at multiple levels. Overall, our study provides a comprehensive molecular resource for understanding mesoderm diversification in vivo and targeted mesoderm lineage differentiation in vitro.

show abstract

The effects of the excision of Hensen's node on the early development of the chick embryo

Cited by 63 publications

References 23 publications

Changes in dorsoventral but not rostrocaudal regionalization of the chick neural tube in the absence of cranial notochord, as revealed by expression of Engrailed‐2

Changes in dorsoventral but not rostrocaudal regionalization of the chick neural tube in the absence of cranial notochord, as revealed by expression of Engrailed‐2

Positional control of mesoderm movement and fate during avian gastrulation and neurulation

Transcriptomic landscape of the primitive streak

Contact Info

Product

Resources

About