Previous analysis of the hemoglobin phenotype of the K562 human erythroleukemia cell line showed regulated expression of the e, J-. y, a-, and &globin genes. Expression of the p-globin genes has not been previously detected in this cell line. In this report, we describe the isolation of a variant of the K562 cell line that actively expresses @globin messenger RNA (mRNA) and polypeptide and show...

Alpha-thalassemia (α-thal) is a disorder caused by the deletion of single or double α-globin genes, and/or point mutations in the α-globin genes. There are 2 common types of α-globin genes; HBA2 and HBA1. Recently, it has been discovered that the HBA2 gene is replaced by a unique HBA12 gene convert in 5.7% of the Saudi population. The α-globin genes have been emerging as a molecular target for ...

High-level beta-globin gene expression is dependent on the presence of the locus control region (LCR), a powerful regulatory element physically characterized by five DNase I-hypersensitive sites (HS), designated HS1-HS5. Of these, HS3 contains seven GT motifs that are essential for its activity. One of the motifs, GT6, has been shown by in vivo footprinting to display the largest difference in ...

Transcription of globin mRNA sequences from rabbit marrow chromatin was detected by hybridization with globin complementary DNA (cDNA). The presence of newly synthesized RNA in cDNA-globin mRNA hybrids isolated by Cs2SO4 density equilibrium centrifugation required the addition of both rabbit marrow chromatin and DNA-dependent RNA polymerase (Escherichia coli) to the transcription reaction. No g...

To study the expression of globin genes in human cells, human epsilon-globin genes were transferred into a K562 cell line, Bos, which synthesizes very low amounts of epsilon-globin mRNA. A plasmid (pSV2neo-epsilon) containing a complete epsilon-globin gene and 2 kilobases (kb) of 5' flanking DNA as well as a neomycin-resistance gene and a simian virus 40 origin of replication was transfected in...

objective(s): β-thalassemia is one of the most common genetic disorders in the world. as one of the promising treatment strategies, fetal hemoglobin (hb f) can be induced. the present study was an attempt to reactivate the γ-globin gene by introducing a gene construct containing klf1 binding sites to the k562 cell line. materials and methods: a plasmid containing a 192 bp sequence with two repe...

Reactivation of fetal hemoglobin genes has been proposed as a potential therapeutic procedure in patients with -thalassemia, sickle cell disease, or other -hemoglobinopathies. In vitro model systems based on small plasmid globin gene constructs have previously been used in human and mouse erythroleukemic cell lines to study the molecular mechanisms regulating the expression of the fetal human g...

Many abnormal α-chain hemoglobins (Hbs) are caused by single nucleotide mutations in α1- or α2-goblin genes. One of these Hbs is Hb Q-Iran which is resulted from a point mutation at codon 75 of the α1-globin gene (Asp→His). The identification of Hb Q-Iran was observed in two members of a family from the Central Province of Iran. In this study, Globin chain analysis on high performance liquid ch...

The inverse relationship between expression and methylation of -type globin genes is well established. However, little is known about the relationship between expression and methylation of avian -type globin genes. The embryonic globin promoter was unmethylated, and -globin RNA was easily detected in 5-day chicken erythroid cells. A progressive methylation of the CpG dinucleotides in the promot...

In human reticulocytes, the critical balancing of alpha- and beta-globin synthesis may be controlled in part by differential translation of the three major adult globin messenger RNAs (mRNAs), alpha 1, alpha 2, and beta. In this study, we determined, as a parameter of translational efficiency, the relative ribosome loading of these three mRNAs. Using oligonucleotide probes specific for the alph...