Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

MicroRNAs (miRNAs) constitute a large family of noncoding RNAs that function as guide molecules in diverse gene silencing pathways. Current efforts are focused on the regulatory function of miRNAs, while little is known about how these unusual genes themselves are regulated. Here we present the first direct evidence that miRNA genes are transcribed by RNA polymerase II (pol II). The primary miRNA transcripts (pri-miRNAs) contain cap structures as well as poly(A) tails, which are the unique properties of class II gene transcripts. The treatment of human cells with alpha-amanitin decreased the level of pri-miRNAs at a concentration that selectively inhibits pol II activity. Furthermore, chromatin immunoprecipitation analyses show that pol II is physically associated with a miRNA promoter. We also describe, for the first time, the detailed structure of a miRNA gene by determining the promoter and the terminator of mir-23a approximately 27a approximately 24-2. These data indicate that pol II is the main, if not the only, RNA polymerase for miRNA gene transcription. Our study offers a basis for understanding the structure and regulation of miRNA genes.
Which polymerase transcribes pri-miRNAs?

Jan Muhlstein (born 3 July 1949 in Most, Czechoslovakia) is a journalist, German Jewish activist and the former chair of the Union of Progressive Jews in Germany.
Which language or languages is Jan Mühlstein fluent in?

Over the next year, however, the Polish forces were subject to attrition, as the Sejm again refused to raise taxes and pay the army, resulting in mass desertions of unpaid soldiery. The Polish problems were further aggravated by the incompetent leadership of hetman Micha Kazimierz Pac, who obstructed Sobieski's leadership, while the Ottomans continued to receive reinforcements. Nonetheless in 1674 the Commonwealth resumed the offensive, taking advantage of a new Muscovy-Ottoman conflict that year, and the Polish-Ottoman war remained undecided.:275 Sobieski's force of 6,000 defeated 20,000 Turks and Tatars under Ibrahim Shyshman in the battle of Lwow in August 1675.:653 Even after the Battle of Trembowla, the Sejm still refused his pleas for more funds and a larger army.:653 In 1676, after Sobieski's 16,000 withstood the two-week siege of Zurawno, by 100,000 men under Ibrahim Pasha, a new peace treaty was signed, the Treaty of Zurawno.:655 The peace treaty partially reversing those from Buczacz: the Ottomans kept approximately two thirds of the territories they gained in 1672, and the Commonwealth no longer was obliged to pay any kind of tribute to the Empire; a large number of Polish prisoners were released by the Ottomans.

Which happened first, the siege of Żurawno or the Treaty of Żurawno?