A Nakatomi | PubMed Health

PubMed2001

[Transitional pre-B-cell ALL].

An 18-month-old girl was referred to our hospital because of fever and pancytopenia. On admission, her bone marrow nuclear cell count was 45,000/microliter, being mostly blasts with cleaved nuclei. The leukemic cells were negative for peroxidase staining, expressed CD10, CD19, CD34 and sIg mu, and did not express sIg kappa and lambda, corresponding to a minor subpopulation of B cells known as transitional pre-B-cells (TPBs). Since TPB-ALL has been reported only infrequently, the incidence and clinical picture of this rare type of ALL are still uncertain. Extensive immunophenotypic studies to determine the expression of sIg mu, sIg kappa and lambda will provide accurate diagnosis, which is essential for effective management of this condition.

Antigens, CD19↗

PubMed2000

Molecular cloning of cDNA encoding two subunits of calcineurin from scallop testis: demonstration of stage-specific expression during maturation of the testis.

Complementary DNAs encoding two subunits of scallop (Patinopecten yessoensis) testis calcineurin were cloned, and the nucleotide sequences of their coding regions were determined. The deduced amino acid sequences of the catalytic subunit, calcineurin A (486 amino acid residues, M(r) 55,005.91), and the regulatory subunit, calcineurin B (170 residues, M(r) 19,237.67), showed high similarity to those of mammalian calcineurins, especially to the brain-type ones rather than to the testis-specific isoforms. Northern blot analysis showed that only a single species for each subunit was expressed in testis and the expression of each subunit increased dramatically from January to March during the maturation stages of the one-year cycle. The period when the maximum amount of mRNAs for calcineurin was expressed corresponds to the one immediately after meiosis, that is, the maturation stage in which 20-80% of the average testis is occupied by spermatozoa. The result is consistent with the one as to the expression of the testis-specific isoform of calcineurin A in mouse, which occurs immediately after meiosis. This is the first report on the stage-specific expression of calcineurin in invertebrate testis and its sequence similarity to the mammalian brain-type isoforms may indicate that the mammalian testis-specific isoforms appeared in evolution after the divergence of mammals from the mollusks and then diverged rapidly for specific functions in testis.

Amino Acid Sequence↗