A temperature-sensitive mutant, K12, isolated from an established Chinese hamster fibroblast cell line, Wg1A, is used to study the coordinated expression of two genes specifically induced by glucose starvation. When K12 cells are incubated at the nonpermissive temperature (40.5~C), the synthesis of several proteins is specifically induced. Two of the proteins (94 and 78 kilodaltons) are identified as glucose-regulated proteins since the same proteins are overproduced in a variety of animal cells when they are starved of glucose. cDNA clones have been constructed with RNA isolated from hamster K12 cells incubated at 40.5~C. Two of the cDNA clones, by criterion of hybrid-select translation, are shown to code for the 94 and 78 kilodalton proteins. Using these cDNA clones as probes, we show that after 4 hrs of incubation at 40.5~C, there is a 10-fold increase in their corresponding mRNA levels. We demonstrate that the kinetics of transcription of these genes directly parallels the accumulation of the mRNA levels, suggesting that the expression of these two genes is coordinatedly and primarily regulated at the transcription level. In addition, the expression of these two genes is stringently regulated by the availability of glucose in the medium and treatment of cells with calcium ionophore A23187. In order to determine the control signals for these genes, a novel eukaryotic hybrid gene has been constructed from the 5' sequence of a rat gene and the bacterial neomycin resistance gene. Following transfection into hamster fibroblasts, the neomycin transcripts can be induced to high levels by the absence of glucose and A23187 treatment. Further, this hybrid gene can also be regulated by temperature when it is introduced into a temperature-sensitive mutant cell line. Our results indicate that the sequence containing the regulatory/promoter function resides within a 1.25-kb region of the rat genomic sequence. (G)

National Institute of Health (NIH)
National Cancer Institute (NCI)
Method to Extend Research in Time (MERIT) Award (R37)
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Mammalian Genetics Study Section (MGN)
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University of Southern California
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Hussien, Yassir; Podojil, Joseph R; Robinson, Andrew P et al. (2015) ER Chaperone BiP/GRP78 Is Required for Myelinating Cell Survival and Provides Protection during Experimental Autoimmune Encephalomyelitis. J Neurosci 35:15921-33
Zhu, Genyuan; Wang, Miao; Spike, Benjamin et al. (2014) Differential requirement of GRP94 and GRP78 in mammary gland development. Sci Rep 4:5390
Lee, Amy S (2014) Glucose-regulated proteins in cancer: molecular mechanisms and therapeutic potential. Nat Rev Cancer 14:263-76
Gray, Michael J; Mhawech-Fauceglia, Paulette; Yoo, Eunjeong et al. (2013) AKT inhibition mitigates GRP78 (glucose-regulated protein) expression and contribution to chemoresistance in endometrial cancers. Int J Cancer 133:21-30
Luo, B; Lee, A S (2013) The critical roles of endoplasmic reticulum chaperones and unfolded protein response in tumorigenesis and anticancer therapies. Oncogene 32:805-18
Luo, Biquan; Tseng, Chun-Chih; Adams, Gregor B et al. (2013) Deficiency of GRP94 in the hematopoietic system alters proliferation regulators in hematopoietic stem cells. Stem Cells Dev 22:3062-73
Wey, Shiuan; Luo, Biquan; Lee, Amy S (2012) Acute inducible ablation of GRP78 reveals its role in hematopoietic stem cell survival, lymphogenesis and regulation of stress signaling. PLoS One 7:e39047
Pfaffenbach, Kyle T; Pong, Michelle; Morgan, Todd E et al. (2012) GRP78/BiP is a novel downstream target of IGF-1 receptor mediated signaling. J Cell Physiol 227:3803-11
Wey, Shiuan; Luo, Biquan; Tseng, Chun-Chih et al. (2012) Inducible knockout of GRP78/BiP in the hematopoietic system suppresses Pten-null leukemogenesis and AKT oncogenic signaling. Blood 119:817-25

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