Disease relevance of SBDS

• Shwachman-Diamond syndrome (SDS; OMIM 260400) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency, bone marrow dysfunction and metaphyseal chondrodysplasia [1].
• In conclusion, neutropenia and defective chemotaxis did not result in severe clinical infection in SDS [2].
• METHODS: Ten consecutive patients that received radiation therapy for uterine cervical cancer, with the SBDS, between January and May 2003, were included in this study [3].
• Congenital aplastic anemia caused by mutations in the SBDS gene: a rare presentation of Shwachman-Diamond syndrome [4].
• Mutation analysis of SBDS in pediatric acute myeloblastic leukemia [5].

Psychiatry related information on SBDS

• One hundred and ninety two women were assessed in the 38th week of pregnancy (SDS scores), peripartum period (DSM-III-R diagnosis (n=105); SDS scores) and 6 months postpartum (EPDS; n=89) regarding diagnosis of depression, self-ratings of depressive symptoms and levels of estrogen and progesterone [6].
• RESULTS AND DISCUSSION: Maternal weight perception assessments at age 6 months, 12 months, 2 years and 4 years of age were related to body weight status as well as changes in body mass index standard deviation score (BMI-SDS) and skinfold SDS between age at assessment and age 7 [7].
• BACKGROUND: While traditional models of Alzheimer's disease focused on large fibrillar deposits of the Abeta42 amyloid peptide in the brain, recent work suggests that the major pathogenic effects may be attributed to SDS-stable oligomers of Abeta42 [8].

High impact information on SBDS

• We found recurring mutations resulting from gene conversion in 89% of unrelated individuals with SDS (141 of 158), with 60% (95 of 158) carrying two converted alleles [9].
• Archaeal orthologs are located within highly conserved operons that include homologs of RNA-processing genes, suggesting that SDS may be caused by a deficiency in an aspect of RNA metabolism that is essential for development of the exocrine pancreas, hematopoiesis and chrondrogenesis [9].
• Palmitoylation of CD95 facilitates formation of SDS-stable receptor aggregates that initiate apoptosis signaling [10].
• Cysteine 199 mutants no longer form SDS-stable aggregates, and inhibition of palmitoylation reduces internalization of CD95 and activation of caspase-8 [10].
• We now demonstrate that these SDS-stable forms of CD95 correspond to very high molecular weight DISC complexes (hiDISC) and are the sites of caspase-8 activation. hiDISCs are found both inside and outside of detergent-resistant membranes [10].

Chemical compound and disease context of SBDS

• An analysis of inner membrane proteins of Escherichia coli has identified several SDS-resistant protein complexes that separate into subunits upon exposure to TFE [11].
• After purification of cyanobacterial preapo-plastocyanine, its signal sequence can be cleaved off by the E. coli signal peptidase, and protein processing was followed on Coomassie stained SDS polyacrylamide gels [12].
• Methods: A total of 196 obese children [SD score (SDS) of body mass index (BMI): 2.17 +/- 0.03], aged 7-18 years, including 86 male subjects, underwent an oral glucose tolerance test (1.75 g glucose/kg body weight) [13].
• The addition of wild-type SBDS complements the actinomycin D hypersensitivity of SDS patient cells [14].

Biological context of SBDS

• Patient DF269, who carried no detectable gene mutations, expressed wild-type levels of SBDS protein to add further support to the growing body of evidence for additional gene(s) that might contribute to the pathogenesis of the disease phenotype [15].
• Patient SD101 expressed low levels of SBDS protein harboring an R169C missense mutation [15].
• SBDS localization was cell-cycle dependent, with nucleolar localization during G1 and G2 and diffuse nuclear localization during S phase [15].
• Novel SBDS mutations caused by gene conversion in Japanese patients with Shwachman-Diamond syndrome [1].
• The most frequent mutations are due to gene conversion events between SBDS and its unprocessed pseudogene, named SBDSP [16].

Anatomical context of SBDS

• The SBDS protein was detected in both the nucleus and the cytoplasm of normal control fibroblasts, but was particularly concentrated within the nucleolus [15].
• Full-length SBDS protein was not detected in leukocytes of SDS patients with the most common SBDS mutations, consistent with a loss-of-function mechanism [17].
• Irrespective of the ANC in vivo, abnormal CFU-GM was observed in all patients with SDS tested (14 of 14), whereas BFU-E was less often affected (9 of 14) [2].
• Recently, it has been demonstrated by computer-assisted methods that the single behavioral defect of polymorphonuclear leukocytes (PMNs) of SBDS patients is the incapacity to orient correctly in a spatial gradient of chemoattractant [18].
• To investigate the function of the SBDS protein, we undertook loss-of-function experiments in the 32Dcl3 cell line, which has the potential to differentiate to mature neutrophils [19].

Associations of SBDS with chemical compounds

• The SBDS consists of a customized Styrofoam compression device that can displace the small bowel out of the radiation fields and an individualized immobilization abdominal board for easy daily setup of the patient in prone position [20].
• Dialysis of this extract (SBDS) against buffer containing 25% ethylene glycol produced a stable, reconstituted and active preparation (SBDSE) of vesicles which upon centrifugal separation followed by gentle resuspension retained 95-100% [3H] 8-OH-DPAT binding activity as well as 60% [3H] GppNHp binding and adenylate cyclase activities of SBDSE [21].
• Like other envelope precursors, the 210-kD protein became insoluble in SDS and beta-mercaptoethanol on activation of transglutaminases in cultured keratinocytes [22].
• Two polypeptides are present on SDS-gels of the 8 M urea eluent with apparent molecular mass of approximately 210 and 47 kDa [23].
• The secondary structure was similar in three different hydrophobic environments as follows: water/trifluoroethanol, SDS, and membrane vesicles of different compositions [24].

Other interactions of SBDS

• A previous study in SDS patients largely of European ancestry found that most SBDS mutations occurred within a approximately 240-bp region of exon 2 and resulted from gene conversion due to recombination with a pseudogene, SBDSP [1].
• These results exclude TPST1 as the causative gene for SDS [25].
• The SBDS RNAi knockdown cells did not proliferate in G-CSF-containing medium but after 7 days had the appearance of segmented neutrophils [19].

Analytical, diagnostic and therapeutic context of SBDS

• Protein expression of SBDS variants were examined by Western blotting [26].
• The initial CT was taken by use of the SBDS, before the beginning of radiotherapy, and 3 additional CT scans with the SBDS were done in subsequent weeks [27].
• SBDS knockdown cells were analyzed for surface marker expression by flow cytometry and analyzed for the sensitivity to apoptosis-inducing stimuli [19].
• Abdominal ultrasonography (US) obtained at 9 mo for patient 1 and at 10 mo for patient 2 showed diffuse high echogenicity, which raised suspicions of SBDS [28].
• AIMS: The efficacy of the small-bowel displacement system (SBDS) in three-dimensional conformal radiotherapy (3-D CRT) planning for sparing the volume of small bowel is presented for cervical cancer [29].

References