Spectra of gold, emitted from a hollow-cathode discharge, have been recorded with the Lund Fourier transform spectrometer in the region 1800-8000 Å. Complementary photographic spectrograms in the region 800-1900 Å have been obtained using the 10.7 m normal incidence spectrograph at Observatoire de Paris, Meudon. The term analysis has yielded 75 new energy levels of Au II, and improved values are given for the previously known levels of the 5d10, 5d96s, 5d86s2, 5d97s, 5d96d, 5d96p, 5d86s6p and 5d97p configurations. The new levels belong to the 5d86s2, 5d96d, 5d98s, 5d86s6p, 5d97p and 5d76s26p configurations. About 450 identified Au II lines with a wavelength uncertainty of about 1 mÅ are reported. The energy level structure has been studied by using the Slater-Condon parametric method. The ionization limit has been determined to 162950 ± 200 cm−1.

Early B-cell factor (EBF) is a transcription factor suggested as essential for early B-lymphocyte development by findings in mice where the coding gene has been inactivated by homologous disruption. This makes the identification of genetic targets for this transcription factor pertinent for the understanding of early B-cell development. The lack of B29 transcripts, coding for the beta subunit of the B-cell receptor complex, in pro-B cells from EBF-deficient mice suggested that B29 might be a genetic target for EBF. We here present data suggesting that EBF interacts with three independent sites within the mouse B29 promoter. Furthermore, ectopic expression of EBF in HeLa cells activated a B29 promoter-controlled reporter construct 13-fold and induced a low level of expression from the endogenous B29 gene. Finally, mutations in the EBF binding sites diminished B29 promoter activity in pre-B cells while the same mutations did not have as striking an effect on the promoter function in B-cell lines of later differentiation stages. These data suggest that the B29 gene is a genetic target for EBF in early B-cell development.

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