RbcS gene

Figure 4. Effects of 5 upstream region of rbc gene on the promoter activity.

An alternative means for obtaining isolated subunits is provided by expression of the rbcL and rbcS genes from Synechococcus PCC 6301 in E. colL These genes... 

Figure 3 (right). Northern blot analysis. Conditions as in Fig. 1, with the exception that the probe was a 5 portion of the rbcL gene from S. 6803 [7]. The presence of the 2.9 kb transcript suggests that the rbcL and rbcS genes are cotranscribed in S. 6803. 

Mogen BD, MacDonald MH, Leggewie G, Hunt AG (1992) Several distinct types of sequence elements are required for efficient mRNA 3 end formation in a pea rbcS gene. Mol CeU Biol 12(12) 5406-5414... 

Fujiwara S., Tsuzuki M., Kawchi M., Minaka N., and Inouye I. (2001) Molecular phylogeny of the Haptophyta based on the rbc L gene and sequence variation in the spacer region of the rubisco operon. J. Phycol. 37, 121-129. 

Phosphofructokinase deficiency (OMIM 171850) is a rare autosomal recessively inherited disorder. Since red cells contain both M and L submits, mutations affecting the genes coding for these subunits wfil affect enzyme activity. Thus when the PFK deficiency mutation affects only the L subunit, RBCs have only M4 and are PFK deficient. In such cases, there is a mild hemolytic disorder without myopathy. However, when the M subunit is deficient, muscle PFK is virtually absent together with partial PFK deficiency in RBCs, which wfil have only L. Therefore deficiency of the M subunit causes myopathy and a mild hemolytic disorder. 

Pyrimidine-5 -nucleotidases are a group of enzymes dephos-phorylating pyrimidine nucleotides to the corresponding nucleosides. The pyrimidine bases diffuse out of the erythrocyte and the phosphates are retained. Pyrimidine phosphates are present on ribosomes of erythroblasts and reticulocytes, but there are normally no pyrimidines in mature RBCs. Two cytoplasmic forms of the enzyme were identified in the erythrocyte, P5 N-1 and P5 N-2. These enzymes are encoded by different genes and have different molecular properties and substrate specificities. Since there are no known disorders associated with deficiency of P5 N-2, this enzyme will not be further discussed here. 

Homozygous Hemoglobin S (HbSS). In homozygous Hb S, a valine for glutamic acid substitution occurs on both p-globin chains because of the inheritance of mutated P-globin chain genes from both parents. The condition is described as sickle cell anemia or sickle cell disease because of the sickle shaped RBCs that occur when there is a sickle cell crisis and is sometimes written as p p. ... 

The most common cause of iron overload is thalassemia, particularly in the parts of the world where it is prevalent (see earlier section). Indeed, the cardiac complications of iron overload are among the most common causes of death in I-thalassemia major. Sideroblastic anemias are a group of iron-loading disorders, many of which are of unknown cause. In a hereditary type of this disorder, there is deficiency of erythroid specific 5-aminolevulinic acid synthetase in RBC precursors because of mutations involving the X-linked gene that encodes this enzyme. Iron storage is common in patients with congenital dyserythropoietic anemia and may be found in patients with red cell enzyme deficiencies, particularly pyruvate kinase deficiency. ... 

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