Xenopus Bcl-XL selectively protects Rohon-Beard neurons from metamorphic degeneration

Amphibian metamorphosis involves extensive, but selective, neuronal death and turnover, thus sharing many features with mammalian postnatal development. The antiapoptotic protein Bcl-XL plays an important role in postnatal mammalian neuronal survival. It is therefore of interest that accumulation of the mRNA encoding the Xenopus Bcl-XL homologue, termed xR11, increases abruptly in the nervous system, but not in other tissues, during metamorphosis in Xenopus tadpoles. This observation raises the intriguing possibility that xR11 selectively regulates neuronal survival during postembryonic development. To investigate this hypothesis, we overexpressed xR11 in vivo as a green fluorescent protein (GFP)-xR11 fusion protein by using somatic and germinal transgenesis. Somatic gene transfer showed that the fusion protein was effective in counteracting, in a dose-dependent manner, the proapoptotic effects of coexpressed Bax. When GFP-xR11 was expressed from the neuronal β-tubulin promoter by germinal transgenesis we observed neuronal specific expression that was maintained throughout metamorphosis and beyond, into juvenile and adult stages. Confocal microscopy showed GFP-xR11 to be exclusively localized in the mitochondria. Our findings show that GFP-xR11 significantly prolonged Rohon-Beard neuron survival up to the climax of metamorphosis, even in the regressing tadpole tail, whereas in controls these neurons disappeared in early metamorphosis. However, GFP-xR11 expression did not modify the fate of spinal cord motoneurons. The selective protection of Rohon-Beard neurons reveals cell-specific apoptotic pathways and offers approaches to further analyze programmed neuronal turnover during postembryonic development.

Photograph of a young man with a beard, ca. 1885-1890

Cabinet card featuring the bust of an unidentified young man with a long beard. "Goldsmith ECG 374 Main St. Springfield, Mass" refers to the photography business of Edwin C. Goldsmith. The back of the card is blank.

Chester Castle, Chester, England, ca. 1745 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: A plan of the castle of Chester : with additional new works errected by order of ... the Earl of Cholmondeley, whereunto is added a project of four bastions in order to defend the antient walls against a regular seige ... by ... Alexander de Lavaux. R. Parr sculp. It was published by Alexander de Lavaux ca. 1745. Scale [ca. 1:300]. The image inside the map neatline is georeferenced to the surface of the earth and fit to the 'British National Grid' coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows fortification features such as buildings, stables, guard houses, towers, quarters, stairs, gates, parade grounds, arsenals, wells, ground cover, and more. Includes also index.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Chester, England, ca. 1745 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Plan of the city & castle of Chester, survey'd and drawn by Alexander De Lavaux, engineer ; R. Parr sculp. It was published ca. 1745. Scale [ca. 1:3,960]. The image inside the map neatline is georeferenced to the surface of the earth and fit to the 'British National Grid' coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, drainage, built-up areas and selected buildings, fortification, ground cover, and more. Relief shown by hachures.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Blue Beard and, Puss in boots /

Gold cloth binding, with title and design stamped in gilt on front cover; gilt spine title; gilt top edge. Ribbon ties.

Chester area : Randolph County /

"April 8, 1950."

Review report for flood control, Feather River near Chester, California.

Cover title.

The diary of Dr. Thomas Cartwright, bishop of Chester; commencing at the time of his elevation to that see, August M.DC.LXXXVI,; and terminating with the visitation of St. Mary Magdalene college, Oxford, October M.DC.LXXXVII.

Mode of access: Internet.

Chester White journal.

Mode of access: Internet.

Industry builder; the biography of Chester Earl Gray.

Bibliography: p. 225-226.

Remains, historical and literary, connected with the Palatine counties of Lancaster and Chester.

Title varies slightly.

An inquiry how to prevent the small-pox and proceedings of a society for promoting general inoculation at stated periods, and preventing the natural small-pox in Chester /

Mode of access: Internet.

Chester A. Arthur papers [microform].

The surviving bulk of Arthur's papers,most of which are said to have been burned at his direction the day before he died.