Nuclei of nonviable ovine somatic cells develop into lambs after nuclear transplantation.
Here we report on the successful reprogramming of nuclei from somatic cells rendered nonviable by heat treatment. Granulosa cells from adult sheep were heated to nonphysiological temperatures (55 degrees C or 75 degrees C) before their nuclei were injected into enucleated metaphase II oocytes. Reprogramming was demonstrated by the capacity of the reconstructed embryos to develop to the blastocyst stage in vitro and into fetuses and viable offspring in suitable foster mothers. To our knowledge, this is the first report of cloned mammalian offspring originating from nonviable cells. In addition, our experiments show that heat-treating donor nuclei destabilizes higher-order features of chromatin (but leaves intact its nucleosomal organization) and results in a high proportion of reconstructed embryos developing to the blastocyst stage and beyond.
Loi
Pasqualino
P
Dipartimento di Strutture, Funzioni, Patologie e Biotecnologie, Università di Teramo, Piazza Aldo Moro 45, 64100 Teramo, Italy. loi@ifv.vet.unite.it
Clinton
Michael
M
Barboni
Barbara
B
Fulka
Josef
J
Cappai
Pietro
P
Feil
Robert
R
Moor
Robert M
RM
Ptak
Grazyna
G
D000818:Animals; D000831:Animals, Newborn; D001755:Blastocyst / Q000502:physiology; D001973:Bromodeoxyuridine; D002467:Cell Nucleus / Q000502:physiology* / Q000648:ultrastructure; D002468:Cell Physiological Phenomena; D002843:Chromatin / Q000502:physiology / Q000648:ultrastructure; D019976:Cloning, Organism / Q000379:methods*; D004247:DNA / Q000096:biosynthesis; D003850:Deoxyribonuclease I / Q000378:metabolism; D003851:Deoxyribonucleases / Q000502:physiology; D005314:Embryonic and Fetal Development / Q000502:physiology; D005260:Female; D005307:Fertilization in Vitro; D005838:Genotype; D006107:Granulosa Cells / Q000502:physiology* / Q000648:ultrastructure; D018895:Microsatellite Repeats; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000502:physiology; D011247:Pregnancy; D012756:Sheep
D002843:Chromatin; D004247:DNA; D003851:Deoxyribonucleases; D003850:Deoxyribonuclease I; D001973:Bromodeoxyuridine