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This Week in Science: Aug 21, 2009

In early online publication in Science, scientists at the J. Craig Venter Institute led by Sanjay Vashee report cloning a bacterial genome in yeast. Their work cloned a modified Mycoplasma mycoides genome inside a yeast cell as a plasmid, and then transferred that to a Mycoplama capricolum and watched it divide into a viable M. mycoides cell. In order to protect it from being degraded by the recipient bacteria's immune system, "[they] modified the original genome of the bacterium Mycoplasma mycoides, whilst it was inside the yeast cell," says a BBC story. "Then they either attached methyl groups to it, or inactivated the restriction enzyme of the recipient bacterium, before transplanting the genome into its new cell." The work gets the field one step closer to a fully synthetic life form, adds a post at SciAm's 60-Second Science.

An editorial by Wieland Gevers at the University of Cape Town makes the case for globalizing science publishing, especially in Africa. There, he says, many scientists remain outside the established scientific publishing system, "exacerbating the low international recognition and impact of their accomplishments." The situation can be helped by encouraging publishing in local journals and indexing those so they are digitally accessible, he says.

Two papers delve into the regulation of follicular T helper cell differentiation. Follicular T helper cells are one subset of CD4+ T cells, which help B cells respond to an infection by secreting antibodies. In work from Chen Dong and Roza Nurieva at the M.D. Anderson Cancer Center in Houston, measuring Bcl6 expression using qRT-PCR showed that this transcription factor is needed to differentiate follicular T helper cells.

A complementary paper from La Jolla Institute for Allergy and Immunology's Shane Crotty used gene expression microarrays to show that Bcl6 was up-regulated in follicular T helper cells and Blimp-1 was the most down-regulated transcription factor. "These findings demonstrate that [follicular T helper] cells are required for proper B cell responses in vivo and that Bcl6 and Blimp-1 play central but opposing roles in [follicular T helper] differentiation." A perspective offers more.

The Scan

Tens of Millions Saved

The Associated Press writes that vaccines against COVID-19 saved an estimated 20 million lives in their first year.

Supersized Bacterium

NPR reports that researchers have found and characterized a bacterium that is visible to the naked eye.

Also Subvariants

Moderna says its bivalent SARS-CoV-2 vaccine leads to a strong immune response against Omicron subvariants, the Wall Street Journal reports.

Science Papers Present Gene-Edited Mouse Models of Liver Cancer, Hürthle Cell Carcinoma Analysis

In Science this week: a collection of mouse models of primary liver cancer, and more.