Callus was obtained from leaf explants of Cephaelis ipecacuanha on Murashige and Skoog (MS) basal medium supplemented with 0.5 mg/l Kin, 4.0 mg/l 2,4-D and 3% (w/v) sucrose [Murashige, T., Skoog, F., 1962. Plant Physiol. 15, 437±497]. Plantlet regeneration through somatic embryogenesis was achieved on MS medium containing 2.5 mg/l Kin, 1.0 mg/l 2,4-D and 3% (w/v) sucrose. Maturation and germina...

Acute myelogenous leukemia (AML), subgroup M2, is associated with a nonrandom chromosomal translocation, t(8;21)(q22,q22). The oncogene c-mos also has been localized to the q22 band on chromosome 8. There is also evidence that genes on chromosome 21 may be important in the development of leukemia. To determine whether the c-mos oncogene has been translocated in AML-M2 with this translocation an...

X chromosome inactivation occurs early in mammalian development to transcriptionally silence one of the pair of X chromosomes in females. The XIST RNA, a large untranslated RNA that is expressed solely from the inactive X chromosome, is implicated in the process of inactivation. As previous studies have shown that the XIST gene is methylated on the active X chromosome, we have treated a mouse/h...

Chromosomal fusions are common in normal and cancer cells and can produce aberrant gene products that promote transformation. The mechanisms driving these fusions are poorly understood, but recurrent fusions are widespread. This suggests an underlying mechanism, and some authors have proposed a possible role for RNA in this process. The unicellular eukaryote Oxytricha trifallax displays an exor...

It is hard to imagine that all the cells of the human organism (about 10(14)) share identical genome. Moreover, the number of mitoses (about 10(16)) required for the organism's development and maturation during ontogeny suggests that at least a proportion of them could be abnormal leading, thereby, to large-scale genomic alterations in somatic cells. Experimental data do demonstrate such genomi...

The XIST gene, expressed only from the inactive X chromosome, is a critical component of X inactivation. Although apparently unnecessary for maintenance of inactivation, XIST expression is thought to be sufficient for inactivation of genes in cis even when XIST is located abnormally on another chromosome. This repression appears to involve the association of XIST RNA with the chromosome from wh...

We describe a girl with neurofibromatosis type 1 (NF1), mild dysmorphic features, growth and mental retardation, autism, and mosaicism of ring chromosome 17 and chromosome 17 monosomy. The extent of genetic material deleted from the ring chromosome was determined using a combination of classical cytogenetics, fluorescence in situ hybridization (FISH) and multiplex ligation-dependent probe ampli...

A myeloid-related sequence (mrs) has previously been identified that is highly expressed in selected subpopulations of myeloid leukocytes. Nucleotide sequence analysis indicates that mrs encodes what is apparently a unique 93-amino acid protein that includes an 18-amino acid leader sequence. Hybridization of an mrs cDNA probe to a Southern blot made from somatic cell hybrid DNAs shows 100% conc...

The T-cell receptor (TCR) alpha/delta chain locus on chromosome 14q11 is nonrandomly involved in translocations and inversions in human T-cell neoplasms. We have analyzed three acute T-lymphoblastic leukemia samples carrying a t(10;14)(q24;q11) chromosome translocation by means of somatic cell hybrids and molecular cloning. In all cases studied the translocation splits the TCR delta chain locus...

The chromosome numbers and karyotypes of eight species, the subgenus Botryanthus genus Muscari distributed in Turkey were analyzed. These taxa are M. adilii M.B. Güner & H. Duman, anatolicum Cowley Özhatay, bourgaei Baker, latifolium, J. Krik, inconstrictum Rech. f. microstomum P.H. Davis D.C. Staurt, parviflorum Desf. sandrasicum Karlén. Five them (M. adilii, anatolicum, bourgaei, sandrasicum)...