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The mysterious origin of plasma cells and non‐canonical molecules The mystery is not quite of the same magnitude as something penned by Edgar Allen Poe. In the maturation of the immune response, there are twists and turns and hidden passages, strange molecules that suddenly appear. B cells must be transmogrified to plasma cells and the plasma cells supplied with large quantities of new rough ER, Golgi and mitochondria. After being proteomically examined by Vetterman et al., much less remains hidden in the transition from B cell to plasma cell. These workers applied 2‐DE, 2‐D DIGE, MALDI‐TOF, MS, and Western blots. Chaperones and secretion cofactors materialize. A total of 32 differentially expressed proteins are identified, but estimates still suggest that we have identified only 2% of the B‐cell proteome. pp. 1228–1237Ionizing radiation as therapy: Blunderbuss or target pistol The effectiveness of ionizing radiation (IR) therapy has been difficult to establish quickly for want of specific reporter proteins, particularly tissue‐specific markers. In the study reported here, Lim et al. analyzed changes in protein expression in four mouse tissues harvested one day after whole‐body exposure to 1 Gy 137 Cs. Organs were stored in liquid nitrogen until used. Spots from 2‐D gels were extracted, digested with trypsin and analyzed by MALDI TOF/TOF. A total of 3532 spots were well defined, but only 25 unique proteins were identified. Of those, two were further examined and looked like real possibilities: phosphoglycerate kinase 1 (indicator for intestine) and transaldolase 1 (for brain) by 2‐D. Unfortunately, the picture is not so clear with closer examination. Brain cells are highly resistant to IR. More work is needed. pp. 1254–1263And anuddah contendah entahs da mass spec ring: Here's 193 nm UVPD With almost clock‐like regularity, new mass spec‐based methods of peptide sequencing appear in the proteomics literature. Sometimes it's a case of “Mine's bigger than yours” or “Mine's longer than yours” or “Mine's shinier than yours”. I think what we have here is “Mine is more properly sized than yours”. Madsen et al. have examined the results of using a 193 nM UV laser (rather than 262 nm) to dissociate peptides and report here that the energy is well matched. Sequence coverage ranges from 85 to 100% with little averaging; sites of phosphorylation are revealed consistently as a result. The one bias of the system was the increased signal from peptides containing above average numbers of aromatic amino acids. The laser used in this work was an ArF excimer coupled to a linear ion trap. Another feature of the 193 unit: 5 ns pulses dramatically improve throughput. pp. 1329–1334